Did it at 40. Left a dead end career in IT after yet another layoff, and became a mailman. It's really not so bad. I make just as much as I did in IT, which is a real indictment of IT, and most days I'm done by 2pm. There are some times around Christmas where I might cover extra routes for the money, in which case I'm working until 8pm. But that is completely my choice, and I get paid very well for doing it. One pay period during Christmas, I got the extra route pay plus a boot allowance which doubled my pay for those 2 weeks. That would never happen in IT. The best I could hope for after getting the 2am emergency call was that I got to work from home the next day (pre-pandemic). That's it. No extra pay, no extra time off, because my "on-call" pay apparently covered that. And I didn't make any more than my base pay as a mailman. This was really the best decision I've ever made.
I'm in Canada, in an area heavy with tech companies. But I was also stuck in Support. I took a Support job since a friend was working there and they offered me almost double what I was making as a QA developer, which that point was completely lost on the people I had been working for. But that was the worst decision of my life. They promised me a chance to move to C# development if I started in Support, which is a big part of why I took the job. After 5 years of broken promises, they laid me off unceremoniously. After that, it was just a string of shitty support jobs at about the same wage each time. My salary had stagnated for a decade. New developers were starting at more than I was making after 10 years. So after spending more than a year looking for a job after the last layoff, I was desperate and starting applying to everything. This job came up, and after a few more months of apply to IT and coming very close to not one but two different developer roles that both evaporated after I was told I had the second interview with the director, I decided being a mailman wasn't so bad. I just stopped apply to IT and embraced it.