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/
Amusingly enough, your assertion here is functionally identical to the one you’re criticizing.
Your assertion is that it’s not worth engaging with those who advocate for preemptive defederation because their fundamental nature makes it such that you cannot legitimately expect a positive outcome.
And that’s EXACTLY the position that those in favor of preemptive defederation have taken regarding Meta.