What we have today is a pandemic, economic depression, and world war, all rolled into one. We may become nostalgic for the old days when they came one at a time.
(I say world war, because we have multiple conditions that resemble or simulate war. There is a geopolitical battle between the US and China that runs barely in the background. There is a suspension of trade. Free-market economic forces are on lock-down, and we're being asked to unite, sacrifice, and work for 'victory.' Extraordinary regulation, surveillance, and control by the government are now conceivable even in the West. Last but not least, if you're careless or unlucky, you can become one of the casualties, anywhere in the world.)
The key reason to doubt a return to any 'normalcy' is that, just as happened across the two world wars of the past, the world system is in the middle of a major transition.
History may be viewed as a series of strong and weak phases of the US-led world system. (This is a simple but IMO effective framework for people with limited inside information, that is, all of us.) During a strong phase, the system is confidently leading and imposing its will on the world. During a weak phase, the system must retrench, re-organize itself, and transition to something different in order to survive and thrive again. During this phase, extremely 'crazy' things always seem to happen.
1918 - 1929: Strong Phase. This was a period of fixed exchange rates, but with the dollar beginning to replace gold as global reserves. The supports for the system were US growth and financial strength, with Germany having decidedly been neutralized as a threat to the system by World War I. The results were renewed globalization and a general condition of prosperity and peace across the West.
1929 - 1945: Weak Phase. Financial asset values and economic demand collapsed and the dollar had to be devalued against gold. Even this had to be coupled with a ban on private gold ownership in the US to keep the system stable. To keep peace with a shocked and suffering public in the US, fiscal stimulus on a large scale was used, with limited effect. Globalization collapsed and political extremism took root abroad under even worse economic conditions. All of this, eventually, took a second world war to resolve.
1945 - 1971: Strong Phase. Another period of fixed exchange rates, but with the dollar totally dominating global reserves. A major factor of stability was that the world had decided to give unconditional love to the dollar, in concert with the Bretton Woods foundational institutions, whose terms were dictated by the US as the biggest victor of the war. Another major support was pulling a Western middle class into the winning alliance, with advances in educational and other social-democratic benefits. This formed a strong political consensus in favor of the West's dealings with the developing world and the Soviet Union. Financial-institution excesses were contained by strong regulation. Globalization proceeded economically but not financially (but this proved eventually unsustainable.) Even with the Soviet Union as a constant threat to the system, the result was a prosperity in the West that reached the majority of the public.
(I chose 1971 somewhat arbitrarily as the end of this period. The system had been gradually weakening during the 1960s. The US, as is human nature, took advantage of its strength to live beyond its means via the dollar system and its trade with Western Europe and Japan. 1971 was a symbolic end-of-era because, that year, a run on US gold by European governments finally forced the US to default on the dollar's convertibility to gold at a fixed rate.)
1971 - 1982: Weak Phase. In effect, the dollar was vastly devalued against gold, and the West entered a floating exchange rate system. Financial assets performed poorly. Economic pain was shared between stagnation and inflation, as the system adjusted to the reality of yet another loss of faith in its foundation, the dollar. Support from the new petro-dollar system forced on Saudi Arabian rulers and other oil producers proved insufficient, and eventually the US had to endure a serious bout of high interest rates and recession to restore faith in the dollar. This decade of 'malaise' also saw the loss of the Vietnam War, as well as the peaking of educational attainment by the US public.
1982 - 2000: Strong Phase The dollar advanced or held steady against gold. Advertised as a return to free-market policies, Western bankers were invited back into the winning alliance, and the Western middle class 'invited' out. Also invited in are developing-world producers and governments, in the form of full-blown globalization, with a big US asset bubble as side effect. The fighting and winning of the Cold War also became a major support and boost to the system. In particular, China's vast labor pool and cheap currency became one of the great supports. Inequality and financialization (the buildup of financial assets and their values) had begun, but this period is remembered for the 'goldilocks' conditions of low interest rates, low inflation, and high GDP, in the West. Most Westerners were at least able to enjoy stable or declining prices, as a result of globalization.
2000 - ?: Weak Phase. The dollar was 'devalued' against gold several fold. Competitive devaluations among major currencies occurred (especially after the 2008 crisis.) Major declines of asset values occurred in 2000-1, 2008-9, and 2020. On the surface, low interest, low inflation and decent GDP numbers were maintained in the US, but without the energetic zeitgeist of the previous period. Economically it's been a period of muddling through, with Western central banks loosening money to stave off crisis and buy time, while blowing serial bubbles. Geopolitically and politically, the US-led system suffered a series of setbacks, as against Iran and Russia, with China eventually becoming hostile (though after helping with post-2008 crisis management) and with unhelpful nationalist and isolationist populism growing in the West itself. In 2020, a coronavirus global pandemic shut down the entire economy.
Since this is the stage set for the 2020 pandemic, it's hard to see how things can 'return to normal' after it completes its course. At best, the authorities will patch things up as they did in 2001 and 2009, for some more muddling through. But this will only further increase the imbalances currently in the system (one of which is that inequality and financial instability have been reinforcing each other,) and set the stage for an even bigger crisis, perhaps a decade down the road. (We note that each crisis has been worse than the previous one during this period.) Since part of the core nature of the Western system is that the elites are incentivized to destabilize their own system, the more imbalance there is, the more perverse the incentives will become, and the bigger the next crisis.
However, an alternative outcome after 2020 is that an entirely new global order will emerge. Any economic pain and authoritarianism necessary to transition to this world can be blamed on the pandemic. With China, Russia, and other more or less independent centers of power likely still standing, the new arrangements will likely be negotiated rather than dictated. I can only speculate that the following are possible features of a new 'strong phase:'
For the economy, technology will take center stage as the new engine of growth. This will both preserve the West's pre-eminent seat at the economic table and have the 'desired' side effect of enabling more regulation and control by the state for maintaining the system (see below.)
For money and finance, there will be a big move towards a cashless system in the West, which will enable meaningfully negative interest rates -- a major new tool for authorities to deal with crises in the future. In addition, it's possible that the totally fiat money system since 1971 will be blamed for the financial instability since then, and overt exchange-rate targets (or ranges) will be set against non-state monies by Western central banks. Either way, there should be a big 'devaluation' against these monies to stabilize the system to start with.
In politics, surveillance and regulation by the state (to keep the system stable) will become stronger and will be rationalized as necessary for avoiding economic pain from a crisis (as evidenced by the severe economic pain from the pandemic.) This will be stronger in China and Russia than in the West, but all countries will go in this direction, with the West having 'private' entities like Google and Facebook do this work.
Geopolitical developments are difficult to predict at this time. The only guess I can make is that major rivals of the West will be handled more or less peacefully for a number of decades, until India has matured enough to take over as the new superpower while allowing the US and Europe to have a soft landing. All efforts will be made to avoid Chinese world leadership, as it will likely not be friendly enough to the West to allow a gentle decline.
So, a century's pattern reveals that the system is inherently unstable. When the system is strong, it tends to allow itself to be exploited by its beneficiaries, until eventually it becomes unstable and weak. At those times, it tends to try out different things or bide its time, until it finds the right winning alliance and becomes stable again, for now. Thus, not only does it alternate between strong and weak phases, but each period has quite different features from all the others (even when comparing one strong phase against another.) The severe dislocations we're experiencing now strongly suggest we are at a key transition point. In any case, this will be a good opportunity for the system to make a transition to a new, stable phase, since any economic pain of the transition can be blamed on the virus. Certainly, the serious imbalances of 2019 and the decade before did not make for stability. There's every likelihood that we will not return to that period.