Bitcoin will moon when all scared and inpatient people have sold their bitcoin and we, the yawny and patient ones have gotten them for cheap.
That is if you can hold long enough. Right now, I don't see btc rising back up to all time high in the near future, instead I see it going down more in the next coming weeks. Nevertheless, you are right that the wisest option right now is to rebuy bit by bit(using the fiat one gained after selling at high prices way back in December if you have some). It also isn't wise to sell in a bearish market unless you have bought at sub 1000$.
Lots of things can happen, and you are right if the person can hold for some time, then it can be a good investment to try, but if you don't have the
knowledge better to think twice, the market is really hard to predict what we know alone is we are expecting that the value will rise up again, to know'when , it's a matter of time, no one really knows the exact timing to ride safely with this system, we just need to trust and continue collecting
coins inside our wallets.