> it's questionable if I learnt anything useful other then how to get hobby DEs working on ancient hardware

I did similar things, and on one hand I feel it’s ok that it’s not all “useful” - it was a hobby after all, but on the other hand I do feel it had benefits - you learned patience, creative thinking, problem solving, and working on those projects for a long stretch of time almost has a meditative effect I felt. I’m sorry that a lot of modern kids probably don’t get to experience this as much as everything is pre-packaged, system-on-a-chip, non-fixable etc. (And people are more careful of how they dispose of computers due to privacy).