To me it sounds like someone "good with computers" but doesn't really know how to program. All that stuff about "commodore 64" and "garage startup" sounds a bit like a smokescreen. OK, you liked playing around with computers as kid. Great, most of us did. And that made you good enough with computers that you got a job at BigCo. Then you got a little lazy and stopped learning new stuff. It happens. This isn't a condemnation.

I don't think BS is going to help. So here are a couple of options. If you really want to do startups and glam and make hundreds of thousands... you'll have to learn how to program in modern ways. It's going to take some time and effort. And you will have to build some real stuff. You might not have the time.. you are in your 40's, and you might not have the real desire to put in the effort. It's not you can't do this, you probably can but it's going to be difficult and take some real desire and most important some time and a lot of effort.

Here is another option that might be a better one. Go back to a BigCo. You have a history of job stability. You know about BigCo ways of doing things. You are good with computers. Get a certificate or two if you need to. It's not a million dollars but given the required effort, the pay is pretty decent for sitting at a desk. Forget about the 100K+ salaries you see bandied around. That's for something else.