As a longtime educator, I see a lot of experienced teachers leaving. In fact, I'm leaving this year, though I'm unsure if it's permanent.

It's a mixture of reasons, from low pay to high demands, but I think a large part is a lack of respect from students, parents and admin. Teachers have been stripped of most of their power to do anything about it. The last year I taught public school a student was verbally abusing others and threatening them in class and I couldn't get him removed. It ruined the class and scared other students, but because he had documented issues they said they couldn't do anything.

I teach in overseas private schools now, and the kids are fantastic and the pay is decent, but the job has an increasing amount of non-teaching related stuff which detracts from the what matters, the kids. Also, the syllabus for CS is so outdated, and I find myself apologizing to the kids since I need to to teach it to them for their exams. I teach around the syllabus as best I can, but you still need to get results.

TLDR: Experienced teachers leaving, lack of autonomy, curriculum suck