Systemic data collection and casual access aren’t equal.
That said, on these protocols you can’t control it anyway, so it’s not like you can stop it.
They could have been scraping it for years (if they cared) and you’d never know.
Federating won’t give them anything new except DMs to their users since those aren’t encrypted.
All the existing stuff you’ve posted publicly is already public.
Meta will find a way to get their hands on that.