I can think of one reason via experience. I have a law degree and practiced law for 13 years before stopping when we had our second child. My wife is a physician and we could not both maintain our careers and fulfill our parental responsibilities. I taught at a small school for two years which fell apart in 2015. I then got a masters in US History. Since then I have been looking for work and have applied for dozens of jobs. I cannot even generally get an interview even for middle and high school positions. It is difficult to get substitute appointments. I was told for one long term sub position (January to May) there were over 100 applicants. I went to a job fair at the University of Virginia which was overflowing with history and English majors. I believe there were more applicants there than teaching positions in the entire state (a little exaggeration here, but not that much). I keep hearing about the shortage of good teachers, which is true for math and the hard sciences. But in the humanities there is a glut. I can see why so many are depressed. Fortunately for me, I get a rare opportunity, the ability to spend a lot of time with my young children. My youngest is 5 now though and will be in school fulltime in the fall. I would like to get back to fulltime employment but that seems unlikely in the near future. I created a blog (some articles posted here) because history is such a fascinating subject to research and write about. It is discouraging to say the least that with a passion and significant educational background that I can't even get interviews.
It's bad, yeah. During my first year of grad school, I thought the situation was ripe for journalists to come in and expose the terrible conditions young scientists were expected to operate in. Then I realized that there's somewhat of an institutional buffer that had long been installed, and there's some validity in the "right of passage" approach. But the pedestal I used to put academia on has since eroded into significant disdain. It's like someone around here hinted at years ago (COUGHmkCOUGH); If you can just obtain your pedigree and move on, that's almost all that matters. Doors will open. And demonizing industry, like I used to do, is quite silly. Although, I did meet a guy from JP Morgan at a party last week, played hard to get, and then talked mad shit about him and financial companies in general later that evening. A current teacher at my old high school saw my little bio at a small museum (of sorts), found me on f-book, and invited me to give a presentation to her current science classes. It went really well, but I couldn't shake the feeling that I was somewhat perpetuating the problem, in that I was quite selective in the information and perspective I gave during the Q&A session on life as a scientist, and grad school especially. I told them it wasn't easy, you had to be able to stomach the maths, and that you're almost never off the clock when you're payed to think. But I didn't mention the kid in the office next door to mine who hung himself, the multiple breakdowns that I've experienced, how I probably couldn't do it without my girl to anchor me, the statistically poor job prospects, the exponentially growing complexity of the problems we're expected to tackle, ever-increasing competition, etc. etc. etc.
There is no path that is going to satisfy the lot of those that need it. It's structural, and unfortunately, those that can make change have little reason to do so. IMO this won't change without protests, or some sort of collapse, which is going to be slow in coming.
There is an un-natural pressure on new grads to perform above their pedigree. And as newly-graduated degreed people enter the job market, there is even pressure on food industry workers to be certified and (officially) educated in their line of work. I find this troubling.