@paulsheprow @nolan @CobaltVelvet @gargron agree with most of the sentiment others already expressed here.
I think org instances are a truly fascinating idea, and for real would love to see this tested out.
I will say, I don't see a whole lot of point in specifically "blocking" brands from creating accounts on other instances, but they should be silenced / banned if they're advertising (in which case why would they bother creating an account)