We had very few PhDs at the top level, they were mostly engineers. Why? The managers were nearly all engineers, and the managers made the decisions on promotions.
I think there were 8 at the top level when I left, maybe one was a PhD. Maybe. The managers were in general not competent to make these judgments on technical grounds, so they made them on "other" grounds, who could suck up the most was one of them. And it helped a lot to have an important rabbi.
I'm not complaining, they paid me a lot for very little, I probably could have made one more level had I pedaled a lot, but I chose to phase out.
I would have been one level from the top, with no chance at the top. I had a choice between staying on a project where my managers were lying about my work, or taking a sinecure. I would be driving home squeezing the steering wheel and thought I need to get away from this. The managers lied that project into existence, the company spent a lot of money on it, and it basically flamed out, though I think they still make the product.
I confronted my direct manager and he told me "You have to exaggerate to get a product over the threshold." Talking to his boss was pointless, and his boss was a lady VP who couldn't understand anything. She was a cheerleader type, man was she DUMB, really really DUMB. I hated having to present to her.
If the project had failed and any of their lies surfaced, they would have blamed me for it. I was very vulnerable.