Well, that's just dysfunctional. If "stakeholders" are that demanding of peoples' time, then they are the problem.
If your culture isn't engineer-driven, you have bigger problems and the number of PMs you have becomes basically irrelevant.
Sure, for 1 or 2 stakeholders. What if there are dozens? Big projects have lots of requirements and lots of people to coordinate. This is not a small task that can just be hand-waved away.
> If your culture isn't engineer-driven..
Engineers are important and there are notable examples of companies being engineer driven, however you are dismissing the vast majority of companies with your statement. Considering a good chunk of startups are CRUD apps on top of a UI framework of some variety, I doubt many tech startups even need to be engineer driven these days.