Most Ph.D.s are unemployable in the field that they did Ph.D. in. There is only say very small pool Ph.D. topics which are needed in industry like ML, distributed system, pharmacy etc. Most of the Ph.D. is in fields like humanities, psycology, physics etc. doesn't have many openings in industry.
Someone else mentioned something similar, but some of the Postdoc position are oddly specific.
Like I get the schooling you do prior is supposed to allow you to hyperfocus something, but at the same time, I've seen jobs asking for postdocs with experience in highly niche areas, often cross disciplinary. One I saw was looking for someone with encyclopedic knowledge of some crazy domain specific algorithm at the intersection of two sciences.
Wild guess, but I if I were to bet, I'd bet most people with a PhD or even professional experience in the filed would not have heard of this algorithm.
I guess I've seen similar software jobs, but at least with software I can usually afford the equipment to learn things myself.
This seems pretty off-base to me. A lot of folks with PhD's in physics are working in industry. And a lot of the folks working on distributed systems don't have PhD's in that field.