I got into teaching several years ago, leaving industry behind. It's great! I had gotten a little bit tired of programming other people's stuff. It wasn't the programming itself that was dull, but I found most products that people wanted were actually kind of boring and formulaic. And none of them really worked for the betterment of humanity.
Teaching is a massive challenge. The stuff that I teach in computer science I find to be relatively easy after 20 years in industry, but figuring out how to teach it effectively? That's really, really difficult. Such a great challenge to be able to sink my teeth into—so rewarding. And it's for a good cause.
I'm not opposed to going back to industry work. I'd probably use genAI to get a bunch to get stuff done, too, even though I don't use it for my personal projects. But it would have to be some work that I believed in, that was doing some good in the world. I can imagine working for the county, say, or for a non-profit.
I had a company I'd co-founded with a friend of mine, and Google would feed us work (in advertising, of course). It was getting old, and then Google terminated the program we were working under. I just couldn't get enthusiastic about searching for more clients in that field, so I floated for a bit.
During that time, I started doing ad-hoc free classes as part of a local meetup. And I networked with people at the local community college and state university. Taught a couple one-off courses as an adjunct (they always want adjuncts).
In the meantime, someone who was working for a startup bootcamp found some of my writing and reached out asking if I wanted to work there. So I joined that as an instructor.
And that worked for a while, but then the school and I began to disagree on the direction the curriculum was taking. And I decided it was time to move on. I resigned the position and floated for a bit.
Then, fortuitously, a 9-month contract (with benefits) instructor position opened up at the state university, and I went for it. And got it! I've been there 4 years now.
As for how I do teaching, I write a lot of tutorials. Hundreds of thousands of words of practice. I try to come up with effective plans, and I reflect on what worked and what didn't. I watch other instructors and copy the good stuff. I read books on instruction. I interview past students. I talk to people in industry.
I like programming because I enjoy optimization problems. And teaching is still an optimization problem. "How do I get students to realize durable learning with minimum instruction?" It's just that now what we're "programming" are squishy, non-deterministic humans. They don't always get it immediately right. :) But I love working on how to be more effective as a teacher. I think about it all day, every day.
Like the OP, I lived well within my means my whole life, so I'm doing OK overall. Not enough to retire today, but enough to work for less than my capitalistic potential, and I'm happy to trade 3 months off during the summer for not getting paid at this point.
I was also lucky to buy this house near market minimum so my mortgage is low. We buy virtually everything used and rarely spring for expensive fun stuff (except travel). My car is 27 years old (purchased new), gets 37 MPG, and I do routine maintenance myself. I commute on a $200 bicycle.
And I'm lucky to be GenX so I was able to navigate a relative sane economy during the majority of my work years, and my college was 5x cheaper than it is now (inflation adjusted). (When I tell my students my junior college charged $6/unit when I went there, their brains simply reject that information out of hand.)
Also, CS instructors can often command a higher salary since they're looking at a MASSIVE paycut to move out of industry into a college salary scale. And it was really hard to recruit near the COVID peak when I was hired. So I get paid pretty well for an instructor, probably 45% of what I could earn in industry. :) Part of that is made up for with a pension, good health insurance, and unpaid summers off. (That's actually a double-edged sword. Your entire time-off schedule is set from above every year with zero flexibility. I accrue zero days of PTO annually.)
Working for private schools pays more, but the salad days of the online school are behind us, currently.
Teaching is a massive challenge. The stuff that I teach in computer science I find to be relatively easy after 20 years in industry, but figuring out how to teach it effectively? That's really, really difficult. Such a great challenge to be able to sink my teeth into—so rewarding. And it's for a good cause.
I'm not opposed to going back to industry work. I'd probably use genAI to get a bunch to get stuff done, too, even though I don't use it for my personal projects. But it would have to be some work that I believed in, that was doing some good in the world. I can imagine working for the county, say, or for a non-profit.