I recently emailed somebody a few quotes from Freeman Dyson on the PhD system, which I include below. I can track down the sources when I'm back in my office, although anybody can find them easily enough. Dyson is not obscure.

“I’m very proud of not having a Ph.D. I think the Ph.D. system is an abomination. It was invented as a system for educating German professors in the 19th century, and it works well under those conditions. It’s good for a very small number of people who are going to spend their lives being professors. But it has become now a kind of union card that you have to have in order to have a job, whether it’s being a professor or other things, and it’s quite inappropriate for that. It forces people to waste years and years of their lives sort of pretending to do research for which they’re not at all well-suited. In the end, they have this piece of paper which says they’re qualified, but it really doesn’t mean anything. The Ph.D. takes far too long and discourages women from becoming scientists, which I consider a great tragedy. So I have opposed it all my life without any success at all.”

From a different interview:

“Well, I think it actually is very destructive. I'm now retired, but when I was a professor here [Institute for Advanced Study in Princeton], my real job was to be a psychiatric nurse. There were all these young people who came to the institute, and my job was to be there so they could cry on my shoulder and tell me what a hard time they were having. And it was a very tough situation for these young people. They come here. They have one or two years and they're supposed to do something brilliant. They're under terrible pressure — not from us, but from them.

So, actually, I've had three of them who I would say were just casualties who I'm responsible for. One of them killed himself, and two of them ended up in mental institutions. And I should've been able to take care of them, but I didn't. I blame the Ph.D. system for these tragedies. And it really does destroy people. If they weren't under that kind of pressure, they could all have been happy people doing useful stuff. Anyhow, so that's my diatribe. But I really have seen that happen.

And also, of course, it wastes a tremendous amount of time — especially for women, it's particularly badly timed.

If they're doing a Ph.D., they have a conflict between raising a family or finishing the degree, which is just at the worst time — between the ages of 25 to 30 or whatever it is. It ruins the five years of their lives.

And I see the difference in the business world. My daughter happens to be a businesswoman, so I meet a lot of her young friends.

The life there is so much easier for women. They start a company when they're 20; they go bust when they're 22. [Laughs] Meanwhile, they have a kid, and nobody condemns them for going bust. If you're in the business world, that's what's expected: You should go bust and then start again on something else. So it's a much more relaxed kind of a culture. It's also competitive, but not in such a vicious way. I think the academic world is actually much more destructive of young people.

[The Ph.D. system] was designed for a job in academics. And it works really well if you really want to be an academic, and the system actually works quite well. So for people who have the gift and like to go spend their lives as scholars, it's fine. But the trouble is that it's become a kind of a meal ticket — you can't get a job if you don't have a Ph.D. So all sorts of people go into it who are quite unsuited to it. [...]

Anyway, so, I'm happy that I've raised six kids, and not one of them is a Ph.D.”