A bit pedantic, but this is more product management. Not design.
I'm fairly biased here, but I'd argue that product vision is often best executed in the hands of product designers rather than PMs. Having a design leader who takes the product or feature from high level goals, to flows & interactions, and finally down to the pixels often leads to a less-compromised end result. I usually find that singular vision beats design-by-committee.
Of course, this rarely happens due to company politics, which PMs tend to excel at versus designers.
As egotistical and tyrannical as PMs can sometimes be, I have learned to appreciate their function... however, they love to believe that they are miniature CEOs which is hilarious and incredibly annoying at the same time. Designers in lead roles don’t seem to have this problem. Maybe it comes with the MBA.