Anyone ever consider hanging up the office gig and pursuing a career in teaching Tech/IT? I’ve been part of a mentorship program at work for university kids, and it’s probably the most rewarding work I’ve done in a long time. I know the pay would be much less, but maybe I wouldn’t die of a heart attack at 50 like I’m heading for now?

I love teaching people as much as I love learning, but I love teaching computers a lot more.
Go for it if that's what your 50hz heart tells you, passionate and knowledgeable teachers are ALWAYS needed, and touching many lives instead of just managing your own may give you something you think you'll miss about your current job.
Also, you don't really have to give up one or the other, you can teach on your free time or switch and do the opposite.

@c3r38r170 Solid advice