Commercial entities can operate on the #Fediverse, provided everyone is free to completely mute them and defederate from them.
But: it's highly unlikely I'll be interested enough to follow any account operating transactionally with its audience, or in a marketing capacity, or fake engagement, etc. So, if there's a significant number like me, commercial activity will have a much more difficult time on the Fediverse than on centralised platforms; and IMO that's as it should be.