Nostr is a bit different - you own a private key that signs any message (and action, but it's all JSON blobs) locally in your app and then you just broadcast these signed messages to servers ("relays") that cache and relay these to other relays or users. Other users can use your public key to cryptographically verify that the message is from you. The benefit is that you fully own your data, you can later decide to rebroadcast it to any other set of relays. It's common to have e.g. 20 relays connected from your app.

There is a group of people that care and use it and it works well.

One argument could be made here that decentralization also means that there will be variety of different protocols and solutions and that's ok.