I think that even if EEE is what Facebook is going after here, after a certain point some users will just get fed up with the demands/changes they're making and move to an instance that is incompatible/defederated with Threads and then we're pretty much back at where we're right now.
Like when reddit gave the ultimatum to switch to their app or stop using reddit we didn't really have a 3rd option. However if reddit was in the fediverse we could have just told them to have fun with their new platform while the rest of us stay with the old one among ourselves. Sure, you'll still lose majority of the content there but when it comes to threads we're not really interested in their content in the first place so it doesn't matter. If a Lemmy user is willing to play by Facebook's rules just so that they can stay connected to a bigger userbase then I'm not sure if we're actually losing anything of a value if and when our ways apart. Facebook can poison the majority of the fediverse but there's not much they can do with the instances that don't care if they get defederated or not. The niche instances will continue existing.
I'm not personally against my instance blocking them but I'm strongly against people pushing their values onto others. I would much rather have individual users block that instance if they so wish instead of someone deciding for them. Sure you can always switch instances but what Fedi Garden seems to be doing here is going against the essence of fediverse and bullying instances to do as they want just like we're worried of Facebook doing.