I don’t want to say crypto in general, but Bitcoin in particular was born after the 2008 crisis, as a decentrized form of money, meaning storing value against the inflationary fiat money that the goverments can print in a centralized manner, destroying all your savings. I think any technology that empowers decentralization is positive. Same as fediverse. And in the case of bitcoin, having a decentrized money it’s a really positive tool for freedom to avoid centralizing the power in the governments. But I am curious on knowing why you say that there is no positive uses.

I use Logseq in my PC and my phone and I unse Syncthing to sync the notes accross my devices.

The alternatives already exist and they are build on Nostr and it has different apps/clients to interact with that protocol. For example Olas is a Instagram-like and tik-tok-like app, and there are also many twitter-like or mastodon-like apps such as Amethyst or Damus