If the PM was also an ex-developer and has both product management and development skills this happens a lot less. When the PM knows the Engineering and complexity and code debt cost of shipping a feature then they can self-triage with that additional information and choose not to send it to the developers or to consult with dev and scale it back to something more managable.
Its these professional PM's that have done nothing else other than project mangement or PMP that don't have an understanding of the long term dev. cost of features that cause these systemic issues.
I'm still a big believer in "separation of powers" a la Scrum.
There should be a "Product Owner" that can be anyone really, and in the other side there is a self-managed development team that doesn't include this participant. This gives the team leverage to do things their way and act as a real engineering team.
The reason scrum was killed is because of PMs trying to get themselves into those teams and hijacking the process. Developers hated "PM-based scrum", which is not really scrum at all.
What about PMs that were developers but were awful at it and just played the politics game to get that promotion and never have to see code ever again?
I worked with a few of those where it was horrible, because they were incompetent and unwilling to work to improve across all disciplines. But that says more about the individuals.
IMO "Knowing enough to do damage" is the worst possible situation.
A regular user who's a domain expert is 100x a better PO.
Its these professional PM's that have done nothing else other than project mangement or PMP that don't have an understanding of the long term dev. cost of features that cause these systemic issues.