The thing is that federation is a non-user facing feature if you do it right. The whole point is that you don't need to care where a specific service is. Email, arguably the most successful federated app, exposes the servers as a disambiguation mechanism (which hakfoo do you want to message?) but that's not really that important when you're consuming content.

I could see a "polished" Fediverse app that abstracted away the server concept-- you'd say "I want to read the $subject Lemmy community / $person Mastodon account" and it would aggregate and deduplicate data on multiple servers automagically for a rich feed. Maybe track the emergence or discontinuation of servers and refine the lists.

Then, if you want to be particularly precise about which providers you're working with, you can go in and micro-manage the automatic selections.