It was fun to tinker, but it's questionable if I learnt anything useful other then how to get hobby DEs working on ancient hardware. I guess tangentially I gained an intermediate knowledge of Linux command line tools and some networking concepts.
PuppyLinux [0] ended up being my choice for easy defaults after DSL [1] stagnated. I'm glad to see it's still going and has developed its own ecosystem. Even after I could buy reasonable computers, for a while I took some pride in squeezing performance out of budget computers but ultimately, now that I need to be productive to get paid, it's nice to have computers that "just work" with modern software.
[0] https://puppylinux.com/ [1] https://en.wikipedia.org/wiki/Damn_Small_Linux