I've only ever been on projects where the backlog was filled by a PM and or lead engineer and then reviewed collectively and maybe some amount of re-shuffling would take place. Are you saying you've been in meetings where the backlog started empty and it was populate with the entire team in the room?
> I've never seen an empty backlog
How about a backlog with stuff near the top that's no longer relevant or has drastically dropped in importance?
If the top of your backlog is uselessly stale, you're spending too much time writing tickets in the distant past and not enough recently (or maybe congrats on your velocity?). A ticket that's so old it needs to be overhauled to be worked on was written prematurely. This is one of the things kanban is good at.
Edit to add: a team that's heavily reliant on a PM might not be a great fit for kanban? It's not for all teams, and is a natural fit for some
I'll add that kanban means much less time filling a backlog, to the point that an individual can own that, and you're eliminating that meeting.