My understanding is federating with busy instances increases the resources used by that lemmy server. So it’s makes sense to me that an admin blocks whatever they like. This isn’t a paid service, admins are funding this themselves or via very limited donations.

I’m not on lemmy.ml, but from what I’ve read, the majority of users there are dead set against any large corporation looking to encroach on the Fediverse. The mods seem to be following the will of the people.