I don't think that there is any chance of this happening. Platforms want to keep their users on their own platform and not spread across multiple. If your friends are already on one platform chances are that you come to that platform as well.
But I agree that it would be pretty amazing to see happening.
Me too, Sync is an amazing app!
That's what I've been trying to do all this time. Usually searching for !community@instance indexes the community for the instance I'm searching on but in this case it isn't working and seems to be a bug like @[email protected] mentioned in their comment already.
What I want even more is mixed use zoning which would probably improve traffic so much.
Edit: I just saw that they indeed have mixed used zoning!
So you are saying I can only see posts of communities in the all feed that have been indexed by this instance? (Meaning it has been searched for in the search bar)