I have done same, held onto alts until they all went to ashes. Should have converted them into btc or eth. Would be having less regrets today.
My opinion, Bitcoin all time saving mode is the best way. Some time when bitcoin price up then sell and when price down then buy is the best decision.
And imo, Just holding onto btc works fine.
Mate you could have figured it our early, if you could have seen the marketcaps of the shitcoins that you are holding. No altcoin can grow, if it is not backed up by any big organisation or big people. So investing in altcoin is similar to gambling in dice game with 2% chance. The risks involved and profits are always high, but it can eat all your bankroll. Its always safe to invest in coin with big marketcap and popular, so hence Bitcoins and ETH are the best coins available currently with some assurance. Rest is upto you, whether to choose or not.
Well yeah, I figured that out eventually. Expensive lesson though.