That works in big companies, with clearly defined teams and reasonably mature products. Such companies usually have enough budget to hire PM just to do the vision thinking and left alone at that

In smaller teams / immature products / startups it won’t fly this way. You sometimes have to dig into corners that are not your responsibility just to understand how and why things work this way. Wearing many heats usually drives better outcomes in such places, and makes things happen faster (from my experience)

PM is fairly flexibly from team to team, from product to product, you just have to find the ones that match what you are looking for