From a technical perspective, there's nothing stopping FWA from also honoring General bans. There's a reason I called them General and not non-FWA. Read my policy statements carefully - they could even come here and participate in appeals, if they wanted to.
From a practical perspective, though, they don't want to. So, yes, it is what it is. FWA has chosen to disassociate with the rest of the leagues with regards to ban sharing and communications about the system itself. Everything I've done has been to try to minimize the impact of that decision on all leagues in a way I think is fair, and also, to maintain an avenue for the far future if FWA wants to change their mind.
Personally, for what it's worth, I do think some leagues here have acted unreasonably, especially with regards to the proposal to stop ban sharing. But, as I've expressed here and privately, although my goals in this area are to unify leagues, I don't currently personally have time to pursue those goals nowadays. It's sad to see what I've worked for fall apart, but, eh, it's the expected outcome.