We should have something like federated communities
Communities on different instances about the same topic should have the option to essentially federate so a post on one appears on all of them and opening any of them shows you the comments from all of them. This way when lemmy.world is down its not a big deal because posting to any news community federates to all of the communities instead of barely having people see your post. Federation could be decided by the community mods and the comments can have a little “/c/communityname@instance.name” on it so you know which community the comment was originally posted on.
My instance aggressively defends the rights of trans folk and other minorities, so the moderators and the admins of any communities based on our instance will come down hard on transphobes and the like.
That's just not true of most of the rest of the threadiverse though, which means that merging just wouldn't work
That's an important and valid concern. What if the community federation could allow mods on your instance to ban users from other instances? You'd not see that user's posts or comments when viewing a community from your instance. The downside is that your mods would have more work.
Not enough. The idea is to fuck the transphobes off so that they're not welcome in the group, not to give them space to harass some of the members instead of all of the members.