Sounds like you might have content that’s changing? But what you’re running into is exactly what a user would be running into.

No, I just don't there's a specification for what exactly a screen reader is supposed to with ARIA markup.

For example it could show you or read to you a list of all the nav landmarks on the page, which would be (1) helpful for end users, and (2) sure as hell helpful for me as a dev so I can know how the landmarks work as a system. All screen browsers really seem to do is blurt out "NAVIGATION LANDMARK!" randomly before or in the middle or after the <nav>