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.
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
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.