In the 50s there were all sorts of tinkering jobs–think of the repairman who used to come to your house and fix your TV, or your washing machine, or your refrigerator. Nowadays if something breaks you throw it in the trash and buy a new one. I mean that pretty literally, the cost of having a guy come out to take a look at your washing machine, figure out what’s wrong, get the new part, take apart your machine, put in the new part, put it back together, and drive to his next customer can be hundreds of dollars and there’s no guarantee that it will even work, and brand new machine is only slightly more expensive.
There were all sorts of services that sort of still exist, but barely, because new goods are so cheap today and hourly wages are so high. In the 60s and 70s my mom sometimes used to sew her own clothes, nowadays the fabric alone costs more than a finished piece.
So most “computer dude” guys would have been working at some blue collar job back in the 50s. Maybe in a factory, or as a mechanic or builder or tradesman or delivery guy. And that was because most people worked at blue collar jobs. My dad was an electrician for the phone company, but by the 80s they weren’t hiring any more guys at his level, everyone was slowly replaced by computerized systems and modular parts. He never really learned to use computers, but if he had grown up with them today he’d probably be in the IT trenches as a grunt.
Go back a bit farther and most people are still working on farms. Maybe the guy who likes to tinker is the first guy in his area to try mechanized methods instead of mules. Or maybe not, that takes money and everyone is scratching to survive. Plenty of people in those days were happy to take brutal jobs in factories so they could get away from dirt farming.
To look at the trajectory in my family, my great grandfather was a farmer, my grandfather was a carpenter/builder, my father was an electronic tech, and I’m a software QA dude. So those are the jobs I’d probably be doing 50 or 100 years ago. Back in those days you might get a job because you were particularly good at that kind of job, but more likely you got a job that paid the rent and did it well enough not to get fired. Oh, you’ve got an aptitude for mathematics and abstract problem solving? Congratulations, now get on the line and keep inserting tab A into slot B until your shift is over.