Do you not see any value in decentralization? In theory with blockchains, you could replace giant companies with open-source programs that pay for their own server costs with transaction fees, without taking any profit margin off the top. That would be very interesting for stuff like cloud storage and social networks. You can argue it's overly idealistic and may not work out, but you can't pretend there's no value in decentralization

That said, you're free to believe what you want to believe.

Just one thing though, everything you said above I heard hundreds of times before, and there are good explanations for them. I just don't have time to argue here because these are things you can find out on your own if you put your mind into it. (To be honest I don't think I can convince you no matter how I try unless you open up your mind, so I won't try)

Anyway, if you don't care, that's fine too. It's not like not believing in cryptocurrency will doom your future. You'll do fine. And even if the whole thing fails, I'll do fine too. But it's always good to have an open mind about things you don't yet completely understand and try to learn. ("Thinking that you understand completely" doesn't count as actually completely understanding)