I'd block lemmygrad, tbh.
I'm not blocking Lemmy.ml. They are worth a little more than one or two tankie mods. If it skews a little too far that direction, tho... maybe.
With any luck, the community itself will sway larger instances. Smaller ones... who cares?
Lemmy is like email. You only need one account on one server. They all talk together. When you browse all, you browse every post from every Lemmy server. You can subscribe to every user and every post on any other server. You are not limited outside of the rules of the server you join and there are no additional steps needed to do so. Subscribing to them is like subscribing to anyone else.
more below about a potential current situation with Lemmy.
Defederation is a consequence of this kind of setup. At any time, any server owner could defederate another one, making their content unavailable on the one who defederated the other.
This recently happened with beehaw and Lemmy.world. It is currently a bit unsure how this will play out over the next few months, but if I had to wager a guess, Lemmy will not be one place, or one place participated in fully by everyone involved. The experience will be slightly different depending on who you signed up with and their core values.
Choose wisely.