I know exactly what you're talking about. The product manager on the project described above added little value. Luckily, they were so ineffective that they didn't get in the way often. I've had others who were "excellent" at getting in the way.
That said, three of the most impressive people I've ever known are a former marketing exec and two former product managers, all of whom now work in VC. In their former roles, each helped me be the best engineer I could be. The people in their current VC portfolios are lucky to have them as advisors. What makes them so good is that they bring expertise worth listening to, and they clearly value the technical expertise brought by engineers. The result is fantastic collaboration.
They are far from typical, but there are truly great ones out there. Losing hope of that might make it more difficult to be aware of the good fortune of working with one, and maximizing the experience. My hope is that every engineer gets at least one such experience in their career. I was lucky enough to experience it repeatedly, working with at least one great one for about half of my 30-year career.
That said, three of the most impressive people I've ever known are a former marketing exec and two former product managers, all of whom now work in VC. In their former roles, each helped me be the best engineer I could be. The people in their current VC portfolios are lucky to have them as advisors. What makes them so good is that they bring expertise worth listening to, and they clearly value the technical expertise brought by engineers. The result is fantastic collaboration.
They are far from typical, but there are truly great ones out there. Losing hope of that might make it more difficult to be aware of the good fortune of working with one, and maximizing the experience. My hope is that every engineer gets at least one such experience in their career. I was lucky enough to experience it repeatedly, working with at least one great one for about half of my 30-year career.