I am 61 and still working at a tech startup. I love startups. I do not have to work any more (not wealthy due to an exit, but I have enough with normal savings and investments to stop now.) In my line of work (not an engineer, but engineer adjacent, lol) it is unusual for someone my age to be employed- it's a young person's game. But I am fortunate because I have attributes that many lack, including extreme tolerance for ambiguity (at work, not at life.)

I work because I like it. I like being around smart people doing smart things. But in a couple of years, I will stop working and just spend time lifting weights, practicing bjj and painting.