Lemmy is addictive in the same way that attending a routine community center event is addictive - you're happy to come back and see old and new faces, and contribute towards keeping the conversations going.
If you want to set up a new event (instance/community), you can do it yourself, in your own environment, without external pressure.
I would call Facebook, Reddit, IG, etc... more like a casino. You pull constant refreshes for dopamine hits, are fed a stream of ads and content that ostracises you if you don't stay with the current trends, and have no control over your personal data or any works you create.