Academia was crucial in the adoption of UNIX and C, because in the early days UNIX was free beer (AT&T tried to fix that afterwards), so a juicy alternative to paying for Multics, MVS...
That also made UNIX an ideal teaching device for OS programming classes versus the toy OSes developed by students.
Well, until AT&T forbade the circulation of UNIX V6 commented book.
https://en.wikipedia.org/wiki/Lions%27_Commentary_on_UNIX_6t...
What's your opinion on ITS?
I suspect, compared to other OSes of the era (Multics, MVS..), Unix doesn't require too much centralized control of (timeshared) operating system resources; for example the security model is extremely simple. So it was readily adopted in academia, because of this perceived user freedom (you just need a shell and you're good to go), and from there it spread to the industry.
So C and FORTRAN didn't came out of the academia, but were more widely adopted by it, which influenced later generations of students.