My first account on the fediverse was on Beehaw and I was happy with it, but defederating from two of the largest instances gave me a reason to find a new instance. Personally I understand and respect the decision -that is the point of the fediverse afterall.
They had a lot of good communities that will not be cut off from the fastest growing instances which will make things tough to rebuild I think.
I moved from lemmy.world to lemm.ee because of the defederation. Hopefully I don’t have to move again. Better moderation tools will help, I guess, particularly the ability to make restricted communities. But people who suddenly have half or more of their content vanish without notice aren’t going to be convinced to stay on Lemmy.