I actually think this is improvable but I mostly don't care because this isn't as big a complaint as people tend to think it is on the fediverse, the other concerns like "what instance do I pick" tend to be bigger and "oh no my server went down"
That can be improved, we'll talk about that later
So okay, the federation is "message passing" and like email, or physical mail. You have an idea how it works.
Now we need to get to that other thing, a "shared heap" architecture. What on earth does that mean?