In a real world economy, the price of an asset goes up when the demand increases. The demand increases only when the particular assets is circulated throughout the economy and every parties involved in a transaction want to use that assets.
I understand the fact you're trying to explain here, but if we assume based on the dump itself, there must have been a lot of demand from the 20k level till the current 3-4k level range because if it wasn't there, then BTC would have gone straight down to 0 and the value would have ended in grave if and only if there wasn't the demand you're talking about.
Lets take an example of USD. Majority of the world trade are done by USD as a transaction medium. That one factor, keeps the demand of USD higher which push its value to remain at the top. Now lets implement the same rule in crypto world.
I personally believe, regulation will be good for the crypto economy because it will increase the adoption rate which will further increase the circulation on bitcoin pushing the demand higher. Remember, I am not referring to over-regulation here. A simple regulation means an acceptance notification notifying cryptos as a legal tender along with pre-specified tax slabs as per the market standard.
You're correct at one stance that when the demand goes down (esp. for the major crypto like BTC, the whole market including alts and tokens as well as ICOs will see a downfall due to the parent crypto falling to the ground levels). But we're talking about regulations here, and with them, I don't really see average people getting any good profits (considering BTC an asset) when everything will go in the hands of Governments and the so-called institutional investors will surely take charge and throw crypto at such a value where such average investors like us won't be able to buy even 0.01 BTC. They are currently playing with the markets making us helpless to sell almost all our stock to them and this is their biggest win, after which they'll start to take the value up because currently, it's the accumulation phase. Come on! BTC has now come in their eyes and it's not a big deal for them to take control.
If you're saying that crypto should be considered as a legal tender and be allowed to hold the name of a currency, then that's not possible due to it's highly volatile nature and uncertain pumps and dumps.
This kind of regulation will actually encourage a lot of online/offline merchants to begin accepting cryptocurrency as a method of payment alongside fiat. It will encourage a lot of people to take their service fees in cryptos. Overall acceptance rate will be increased which will push the demand and circulation to another notch higher. This is one single factor that can drive immense growth in the crypto market for good!
Merchants are already accepting crypto through various different ways and the only fear for those not accepting it is its volatility, the fear of getting dumped. Regulations with futures are making it possible for big dogs to short it and steal away the remaining BTC in smaller wallets to be added to their huge-sized wallets, this makes them more and more powerful and the one and only thing - cryptocurrencies - which can be bought/sold/traded pseudonymously (even anonymously in some cases) over few centralized as well as decentralized exchanges, will then get into the hands of these bigger authorities who will never let us make the correct use of our rights once again.