[WorldMaker]

Most instance block types in Mastodon affect the "public feeds"/"shared community" on an instance, but allow individual users to follow users on "blocked" instances in their own feeds.

User decision making is still very much an entrenched thing.

Most decision making on blocks in small-to-medium instances is democratic, in my experience, with users voting on them together. Also, as pointed out there's the obvious "vote with your feet" of switching to a different instance if you don't agree with its policies and/or how other instances don't agree with its policies.

There's definitely a risk of large instances trying to strong arm smaller instances with blocks and/or threats of blocks. But so far it's more a philosophical risk than a real risk from what I've seen. At least in my parts of the Fediverse small instances are "the norm" and it's is more likely the blocks are against the larger instances because with size they are more likely to allow spam registrations, they are more likely to have users that don't respect cultural norms like CWs or Alt text/Image Descriptions and don't feel a need to respect them because their mods won't enforce them, or yes they set up an ideologue as a mod/admin and shift to a gross direction. As a "telegraph network between a lot of small villages that mostly ignore the big cities", ActivityPub can be rather nice.