Corporations are driving, for obvious reasons. More supply, cheaper wages, more profits.
FWIW, I think the issues are definitely related though. There's lots of STEM hype in academics as well as in commerce which creates a labor oversupply in both.
The problem is that there are genuine advancements in STEM that are interesting and rewarding, from the academic as well as commercial side, but they're sort of buried in a sea of bullshit, and being able to connect with the worthwhile stuff (financially or otherwise) can often be due to random or sketchy reasons. So people see the great stuff going on, and then either promote it (in the case of politicians and public figures) or pursue it (as someone seeking a career) not realizing that throwing more people at something will necessarily produce more of what we like.
So you end up with the Gallipoli that is modern academics.
Got out of school and story on ground was very different. Wound up programming instead.
I guess their job is to get kids into the program. What happens after doesn't matter so much.
The career path at MIT is work 20 years at MIT then go to a US government funding agency (DARPA, NSF, ONR, etc.) to raise even more money for MIT. These places are staffed 100% by ex-professors (and a few token PhDs who succeeded in industry, to provide political legitimacy "cover".)