How does writing things down help when I don’t remember to read them back…?

It allows me to run any weird combination of applications I feel I need on a given day, (fairly) easily integrating basically all open source packages with a custom/local overlay and have those managed as part of the system just like everything else.

For someone coming from NeXTStep (BSD based), having worked with SCO, various BSD and mostly Linux for the last 20 years, the worst thing about systemd is documentation that’s easily accessible/readable for people used to a traditional init system.

“How do I get it to do special use case X” was a basically unanswerable question when it got dragged into the mainstream (for reasons I can very well understand - the reasons for the dragging, that is, the bad docs, not so much).

Maybe that’s improved in the mean time - I wouldn’t know, I had to figure it out back then and now I know its lingo when searching and such.

I don’t have a ready-to-run solution for you, but I see you already dug quite into that rabbit hole. Google-fu turned up this and this - maybe those are good starting points to have.

For those who like a video format, I found this introduction quite informative.