Nothing really changes since we could just make a non lemmygrad account, just prevents the lemmygrad (and sometimes lemmy) from being seen by "normies" so people can keep the projection that we're anti-LGBT facist nazi sympathizers going longer.
We also can still see their content as we wish through our lemmygrad account and even comment on the "lemmygrad" version of it (not sure if this would be a shared version with lemmy and co but I think they'd also see our comments?), they're just "muting" our community really. The way the fediverse works will we can see their content as long as Lemmygrad doesn't block them back, which I doubt us or Lemmy.ml will be blocking any of these places. for instance we have our own version of 196 thanks to the large "anti-tankie" stance they're taking but haven't blocked the lib version at all.
Our versions of these anti-federation communities may seem smaller but keep in mind our users are more keen on FOSS and supporting this project instead of just making Reddit 2.0 and as such I think the community (here or on lemmy.ml) will show more "heart" than the more close minded instances. After all these groups have a lot of... reddit type behavior in their posts and it's actually a huge turn off for me and others.
With the mass of redditors leaving Reddit it's no surprise that the federation map has so much red around us. I only hope lemmy.world keeps us federated because they feel very much like the link between worlds for me. The users are a mixed bag and full of "RED FASH" libs, but having a community that is large and can decide for themselves by visiting and observing us/our users is much better than this de-fed stuff. Much more in the spirit of FOSS and etc also.