The blockchain’s use of decentralization is pretty much a security measure. If you want to rule out the blockchain entirely, you’d still need to address the immutable and transpartent components. Only using one block once published moving forward is quite different than the fediverse. Then there’s smart contracts too. It’s a massive improvement to various current online platforms, to say it’s merely decentralization is highly misleading.

Edit: So far, web 3.0 has yet to impress me and I’d be surprised if it does anytime soon. But blockchain tech is not simplistic and can be setup for anonymity as well.

It was known before Blockchain that you could do it too. Ancaps just got horny over it and pushed it as the next thing to replace the USD.