I dare say, that 90% of all companies in Europe and US, use Windows. And lots of companies relies heavily on software built 20-30 years ago. Microsoft knows this.
That’s why they are very reluctant to “touch that piece of code from a quarter century ago” because there’s probably a lot of software that would break without it. Software their target audience need.
Students. Students make them that way. It’s no coincidence that most older teachers feel like they’ve checked out.
I did substitute teaching for about two years. I got to see a lot of my old teachers, Some classes were wonderful, a true joy to teach. Others, not so much. I can understand why some people, as you say, mentally check out. It’s a coping mechanism. They were not all the same people I remember. Maybe part of growing older. Maybe part of years of difficult students sucking out all the joy of teaching they had in them