Mastodon isn't it. It has a bunch of inherent problems that can't be rectified. The fact that you are attached to one server for instance. It recreates the problems of email in social media.
It existed for a long time.
Over 1 million users
Somewhat-decentralized
Better user experience than Nostr by far
Better backend and frontend tech
Try https://poster.place to see sample
Discussion
Content wise it is alright though. Apart from the blocking fetish.