That doesn’t prevent power hungry mods from modding hundreds of communities, or mods or admins from enshittifying the most popular communities (or whole instances) with absurd rules or misinformation bots,
Then you jump to a similar community on another instance. In the long term the less restrictive place will win out. When the mods on the lemmy.world politics group nuked one of my highly upvoted submissions many months ago, I stopped submitting there and now all my submissions on that topic go to [email protected] instead. I carefully researched which instance/community has the most reasonable rules. Bottom line is users have much more power on Fediverse than Reddit.
Nothing is stopping you from using a computer as a standalone machine not connected to the internet. Then you have a machine just like the ones in the 1970’s and 1980’s except for having much more memory/processor/diskspace etc. I would say you have a better OS also, except that Linux is basically the same OS as my SCO Xenix 386 I had in the 1980’s.