The Fediverse is a concept that seems to me as real as the Internet or the World Wide Web.

That's like saying webrings didn't exist, only discrete websites.

First rule of the Fediverse: There is no such thing as "The Fediverse"

get out of my head I watched that episode an hour ago

There's definitely a Fediverse. It's a collection of instances with different links to each other determined by each instance and further filtered by users. Just because a particular instance isn't federated with another instance doesn't mean both of them aren't part of the Fediverse.

People will definitely be confused if you explain it badly. They might still be confused if you explain it properly, but in this case that's on you.

I hate the entire fediverse and instance jargon. It is off putting to mainstream users.

The Internet has always been "federated" with "instances". Yet no one ever said, "What email instance do you use."