"[..] But there will also be coins, that will survive and will have to be traded somewhere."

Hence my/ the very first rule of investing in crypto: Make sure there is a working product!

Honestly I've gotten rid of everything that is not working or might not be working in the future no matter how great their concept is, for instance ADA. ADA is great on paper but it might as well never work. Will I be missing out on certain gains short term? There is no denying that.. BUT! Will I come out ahead long term? I'd like to believe that I will. To each their own tho.