But I guess the problem is that every single development position has been converging into this.
The only times in my career as a developer where I was 100% happy was when there was no career PM. Sales, customers, end-users, an engineering manager, another manager, a business owner, a random employee, some rando right out the street... All of those were way better product owners than career PMs in my 25 years of experience.
This is not exactly about competence of the category, it's just about what fits and doesn't. Software development ONLY work when there is a balance of power. PMs have leverage that developers rarely have.
I come from Electrical Engineering. Engineering requires responsibility, but responsibility requires the ability to say "no". PMs, when part of a multi-disciplinary team, make this borderline impossible, and make "being an engineer" synonymous with putting a target on your back.
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.