I think more holding is more pain. If I buy all these coins then it will be sadly twice. I think smarter to make some research and buy promising and good coins only. No life to shitcoins. And in this case, we will sort some altcoins and vote for them.
Yes, the more you hold shitcoins, the more pain you can get. Theres still a risk on holding of course, but Im confident if you hold bitcoin, everything will be good in the future but you must wear good patience.
You can sell those coins that don't grow at all because why you keep your money in them if you know that they won't bring any profit to you
Thats a good idea, because not all coins are worth holding for. You have to choose well on where to put your money especially if you plan to invest for a long time. Long term investing should be in the right place.