I don’t understand how any of these visions fundamentally differ from Mastodon.
Decentralized? Yep. It’s got no center. Open source? Yep, you can fork it and make your own if you want. Unmoderated? Sure, if you want that, you can set up an instance and host whatever illegal content you want. You’ll have a lot of legal problems and most people don’t want it, but the option exists.
Is there any point besides money and crypto bullshit? If you want to post short comments that your friends can subscribe to that isn’t controlled by a big corporation that gives your data to the government… well we have that. It exists. It’s pretty okay. Go use it.