I think the biggest difference between academia and industry stress is that stress in academia is so personal. Your entire career is building up your own personal brand of research, which has to be novel, interesting, reliable, etc. If something goes wrong, like you don't get a grant or you find that you made a mistake or a paper gets rejected, you can't blame your company's leadership for poor decisions, so it's a much more personal reflection on your abilities as a researcher. The rejections are also typically much more often along the lines of "this was a bad idea, I don't know why you spent the past two years doing this" and less like "could you fix your code formatting to match our style guide." And because nearly everyone who does a Ph.D. does it out of their love for the field, feeling like a failure at philosophy is much more personal than introducing a bug or whatever into your code.

a. Advisors have infinitely more power over you then any future manager

b. You can switch jobs but you cant effectively jump gradschool. If I want a change of pace another job is always available.

c. Grad school has greatly diminished returns if terminated early. 5 years of PhD work but no thesis defense means you dont have a PhD. Lots of companies you can just leave and they still count towards your experience.

d. Grad students get paid peanuts, you have to worry about finances. Tech jobs pay a ton, I may worry about promotion but I dont worry about going to a restraunt/buying nice things/etc. If I want something most of the times I just buy it.

All of this makes grad school substantially more stressful than a normal job.

I see I'm interested in the differences of US vs European (continental, e.g. German) system here and to what extent all the American blog posts and comment threads are applicable here.

In Germany it's not considered grad "school", you're a full time "scientific employee" employed by the state and on a somewhat different plane of bureaucracic existence you're also a "doctoral candidate". The pay gap between academia and industry is also much smaller. It surely exists, but a scientific employee gets about 45k eur gross per year. Straight out of a masters it's typically 55-65k, or if you're really good maybe 75 (roughly) .

And I know people who dropped out and found a job without issues. In whst world does it not count as experience that you've mentored masters and bachelor students, probably took part in industry cooperation, traveled the world for conferences and gave talks, did in-house miscellaneous IT work, like you would at a startup.

It's really hard to compare an American PhD student straight out of bachelor's in medieval philosoohy of religion vs a doctoral candidate after a masters in Germany researching, say, machine learning for energy efficiency.

So here are some super rough pre-tax annual numbers for a STEM path in the US (looking at my peers who did physics and some of whom went into ML, which is what I did)

Grad student ~30k

Postdoc ~50k

Assistance professor ~ 100-150k

Distinguished full professor ~ 250k-350k

Industry after masters ~ 100-150k

Industry after PhD ~ 150-300k

Distinguish engineering fellow in industry (physics) >500k

Nowhere even close.

I work at one of the major tech companies. I manage a team and a production system that could cause serious trouble if it went maximally off the rails. I sleep great.

In grad school I had panic attacks. I felt like shit. My self confidence was terrible. And this was despite publishing modestly successfully. In grad school the feedback you get for your work is (as best I can tell) almost entirely random (paper reviews are totally broken). Many people either have a completely absent advisor and no mentorship or a slavedriver who expects you to work insane hours and steals your credit. It does not surprise me even one bit that a huge number of grad students have mental health problems.