PM's responsibility is it ensure product success. Mostly its found in tech companies but now in non-tech as well. Developers develop, designer design, PM .ensures they are developing the right product. What is a right product? One that meets the user needs and helps rhe company achieve business outcomes.
The final buck stops at PM for the product.
Skills required: customer/requirements understanding, data analysis, ui/ux , communication, problem solving, common sense, leadership, foresight, strategy, execution and many many more.
It's a generalist role and not for everyone.