I currently hold some very good coins and made a fortune in 2017 but lost most of it due to the crypto winter... But... now is a great time to stocktake and fill up on more good coins !
mistake number 1:
you think you made profit because they were "good coins"
mistake number 2:
similar to mistake number 1 you think you lost money because of some imaginary thing you are calling "Crypto winter".
the reality is that you participated in a large scale pump and dump. if you sold before the dump began then you made profit and if you were fooled into holding while others dumped you lost a lot of money.
it will be the same scenario in the future too so your last statement about "stockpiling" doesn't even make sense. you are bag holding a bunch of dying coins right now!
My question is.. what's your coin of choice that was very high in price back in 2017 (compared to now) that is most likely to to see massive gains again when the Bitcoin bulls return again soon? I recall BCH doing quite well compared to its current price, for example..
that is a big mistake that anybody can make in altcoin market.
just because some altcoin got pumped big time it doesn't mean it will pump the same size again. in fact it is a well known fact that those coins that are pumped the most won't get pumped the same again because they get dumped the most too and people who are crushed under that dump are not going to trust it ever again.