Fundamentally, I think it doesn't really matter. But as the first commenter said, the point of federation is that you only need 1 account on 1 federated instance to interact with everything. If the app doesn't let you do that, it's just defeating the point.
I second this, intensely! It's very silly...
Is making an account on every instance a thing that should really be done?
Fundamentally, I think it doesn't really matter. But as the first commenter said, the point of federation is that you only need 1 account on 1 federated instance to interact with everything. If the app doesn't let you do that, it's just defeating the point.