I've discovered the same thing about YA fiction, which I've written a bit of. One of the challenges for creating a storyline is how to keep parents and other adults sidelined so that the young people take center stage and resolve whatever the central conflict as.

Some YA authors are much more convincing doing this than others. John Green is a master. Alice Oseman is sort of a rebel. She writes adults who do get involved, and in mostly positive ways.

Anyway, sorry for rambling. I just thought your point was cool.