There is no ideal or correct time for investment. Every time is appropriate if you want to invest long-term. Whoever bought at 2017 ATH can sell now and his investment will have been lost, but we can say that this time is the best time to achieve the maximum possible profit in the shortest possible time?
In theory, it is correct, but the price may be in the area between 25k to 32k at some point in the beginning of next year before the upward line continues. Therefore, now is an appropriate time to achieve maximum profit, but it is not the best.
Calculating Bitcoin's past record gives some idea of when the price of Bitcoin is likely to rise. Usually we see that every 3-4 years Bitcoin has a high pump and ATH build up. But it's hard to say when that will happen. So one should always plan for long term investment and only long term investment can bring a good profit. And a person who only looks for a right time to invest will never find that right time. A few months ago when the price of bitcoin dropped to $15k we were still wondering when is the right time to invest in bitcoin and the price of bitcoin will probably drop further but from there it has now rebounded to 34k which is 2x+ from that time. So rather than finding the right time to invest in Bitcoin, it is wiser to invest instantly and hold patiently.
Yes, by calculating or seeing what has happened in the past, we will also indirectly know what will happen to bitcoin in the future. Although basically the market can always not be predicted accurately but by looking at what is happening now then we will know the potential of bitcoin about where the next price direction will be. True, because the market is always difficult to predict accurately, it is clear that we must have the best planning according to us along with always being firm on the risk management that we have applied, and on the other hand for long-term or short-term problems it depends on everyone's choice, but yes it is true if you want to get a sizable profit then you must implement long-term planning and the key is always patient and consistent. Although we never know for sure about the future of bitcoin but by looking at the statistics of price movements in the past few years it is enough to prove that bitcoin will continue to grow and by implementing long-term planning then you will feel a significant profit.
For the problem of when they should start investing in my opinion it comes back to themselves, because there are also several other factors that might cause them to come late to the investment such as unstable financial problems in their lives which ultimately cause them to lag behind in taking prices that they think are low. And if for example they already have the ability in terms of finance on the other hand they also cannot just immediately allocate their money to the investment, of course there must also be an analysis that must be done to confirm whether the current price is the right price to buy or not by looking at previous movements, determining the support and resistance points, if indeed the price is at the support point (low price) then they can start their investment.
Although it is unpredictable, the past movements of Bitcoin do offer us some indication. Technical analysis can be useful in identifying support and resistance levels, but its also important to take into account outside variables such as changes in the macroeconomic environment and legislative policies. Due to its vulnerability to real-world events, economic downturns, and governmental changes, cryptocurrencies are considered to be high-risk investments.
I like how much you emphasised preparation and risk management. Many people have this problem of deciding between long-term and short-term investments, which is sometimes masked by immediate financial restrictions. In the realm of cryptocurrency, patience and consistency may be virtues, but having a healthy financial buffer is essential before making any purchases. Examining one's financial situation rather than only market developments is essential.