Limits it to the owners of the instances, who are just as (more) vulnerable to pressure from cancel campaigns.
Remember when Gab tried to join the fediverse? A bunch of instance owners got together and agreed to betray the entire premise of the fediverse by blacklisting Gab.
[bla bla bla, i don't support gab, and all other disclaimers]
The "entire premise of the fediverse," to the degree that such a thing exists, is the right of instance owners to choose with whom they federate and not. Blacklisting Gab is the fediverse working as intended.
However, Gab and the like are still there, and you're free to run your own instance and federate with them if you want. Maybe not Gab, last I heard they forked Mastodon and ripped out their federation code.
Remember when Gab tried to join the fediverse? A bunch of instance owners got together and agreed to betray the entire premise of the fediverse by blacklisting Gab.
[bla bla bla, i don't support gab, and all other disclaimers]