You are forgetting the most important aspect of not losing money on trading. Do not sell on a loss. As long as you do not do that, you will have the same amount of Bitcoin as you did before.
If you have the luxury of choosing the time, you will not likely lose, but you will miss the alternative investment opportunity. Whoever bought at a price of 66k will have to wait about 4 years before making profits, and during this period he could have doubled his profits by investing in a different field.
That is absolute nonsense. If he did not buy more Bitcoin at regular intervals, then it is his own fault for missing investment opportunities. And unless you think that every trader has psychic powers to see into the future, then it is impossible to predict such opportunities. If people were to trade on whims, then they would definitely lose their money.
DCA and HODL are and remain the best strategies, in my view.
I'm still not sure what you mean by "the luxury of choosing the time." If he has extra money that he can use to invest, then he does have the luxury of choosing when to invest and how to invest.