It should come as no surprise that the lemmy.ml admin team took about 2 minutes to decide to pre-emptively block threats / Meta. Their transparent and opportunistic scheme to commodify the fediverse and it’s users will not be allowed to proceed.
We strongly encourage other instance administrators to do the same, given the grave threat they pose to the fediverse.
You cannot block whole instances as a user as of now. It might be a feature in the future. If someone wants that, they can go have a look at Lemmy’s GitHub and open an issue for adding this feature in case such an issue does not already exist.