(b) less likely is, well, less likely. Better but not of use, as seen in the linked issue you can easily "loose" access to 19000 other people, just due to one a

(b) less likely is, well, less likely. Better but not of use, as seen in the linked issue you can easily "loose" access to 19000 other people, just due to one admin with whatever reasoning, good or bad, they have - in a "Fediverse" it should be never the decision of the admin for the users. At least if the goal is not having silos and decentralization.