A growing number of instances (mainly of Mastodon so far) are signing an ‘Anti-Meta Fedi Pact’, pledging to block any instance owned by Meta in the fediverse.
I don’t know how big this will get or how effective it will be, but if you run a fediverse instance, you should take a look at this https://fedipact.online/
Who’s to say nazis aren’t meeting in secret right now? You still punch them in their fashy faces when they try to hold rallies on the street.
There is a cost to being relegated to the shadows we should be eager to make them pay.
There is likewise a value to people seeing Meta shunned.
Just because, “they could do it anyway” doesn’t mean we should resign ourselves to them doing it openly much less collaborate with their doing it.