So, when I visit the profile of someone on a different instance, and Mastodon won't show me most of the accounts they're following, that's because those accounts aren't federated to my instance?

That seems undesirable. I really like the idea of decentralized social media, but if it isn't easy to reach from one node to another, it will never fill the niche now occupied by the big VC-backed guys.

@VinnieTesla it's showing you heir profile (name, bio, numbers) and all the toots known to your instance.
If at least one person on your instance follows them, you will have all their recent toots. (but you can click on their picture to go to their instance's public profile, which has all their public toots, and "import" any toot by putting its URL in the search box here)

@CobaltVelvet Thank you, Mommy. 😁 . I was referring specifically to when I try to view the list of accounts that account is following. I'm still trying to see who I know is #onhere somewhere, and traversing the network is an important part of that.

going to their profile on their instance; then, when I find someone else I want to follow, typing the full user name in the search box, works, but it feels inelegant (kind of like the syntax of this sentence).