As someone who went from a technical role (director/architect) into PM, I selected out pretty fast.
When I looked at the differences across organizations where I had worked with other Product Managers, between the ones who selected out, survived, succeeded, and the ones who were great, there were themes.
The great ones (I met two), were charismatic, flexible, technical enough to make engineers feel appreciated, and were the kinds of people who radiated enthusiasm and success. Think ivy grad confidence with an evangelist belief in their product. Likable, clearly on their way to bigger things.
Ones who just succeeded were strong organizational influencers and operators who practically hid their technical understanding, and made it incumbent on more technical people to explain themselves. They kept others talking while they moved pieces and pulled strings. M.Sc/PhD types, classic org power players.
The survivors were corporate natives who brought professionalism to the startups I was at. A few did time in Big 5 consultancies. Often adjacent to confusion, always useful to someone, albeit never clearly to whom. They were experts at allegiances and light relationships and I admired how they managed both the constant contempt from engineering and the relentless outrage of the sales team. They were teflon strong.
People who selected out (I among them) or who rode a product into the ground were a mixed bag of experiments gone wrong. The marketing person with a programming course, the legacy team member, the polymath everyone thought someone else understood, "the only person who understands how it works," the patsy, the brown shoes and patagonia vest guy, the founder in training, etc.
Where I've seen PMs fail seemed to be the result of failing to maintain a balance of flexibility, credibility, and coherence.
There are lots of ways to succeed as a PM and it's a very cool job. It's a rare area where a magic touch is both required and rewarded.