I signed up with beehaw first, but realized that they were defederated from lemmygrad, which I wanted access to. As I became more acquainted with lemmy and started looking into the "flavors" of the different instances, I joined lemmy.ml because they are unapologetic communists and won't defederate with lemmygrad.
As an aside, it's fucking insane to me that lemmygrad is so controversial yet there's crickets about exploding-heads and people are happy to be on instances that don't block them. Cool