Another interesting tidbit from the #Gitlab #ActivityPub thread which may well also apply to other #fediverse software:

"This also is a rich target IMHO for very, very large organizations, such as the US federal government and the States, which consists of various departments, ... and partners that ...need separate control over instances but need ...controlled collaboration across them."

That kind of thing was one of the original uses cases @evan had been working on back in the days, right?