When you’re instance banned and try to post to a community that is going to an instance you’re banned from it will appear as if you’re posting in that community like normal, but the post won’t federate. Only users native to their instance will be able to see the posts (in Leni’s case, only lemm.ee users can see those posts). Let’s say you’re instance banned from lemmy.world. You could seemingly post to a lemmy.world community, but the post won’t actually show up for lemmy.world users.

That's what I mean. It still has an audience. It just uses the programming done to block people, which is the reverse than how blocking works on other websites. Those people can't see it, but the post can still be popular, especially if it wasn't popular in the instance the person is banned from. The fediverse was made backwards.

I don’t know why you seem so insistent on trying to say they aren’t.

Not what I was getting at, as it's not as if there is no impact. Though they can technically ban her from those individual communities anytime they want. They just haven't, except for Davel.

Leni attempted to post in a Beehaw community. Leni is instance-banned from Beehaw. This post isn’t visible to anyone on the Beehaw instance.

No, but it's not invisible. This has been a major negative point about the fediverse. She can, for example, advertise some shit in link form and get traffic, minus any mod being able to do anything about it, because they can't see it. But other people can.