I think it’s fine. Script kiddie is a strict subset of “hacker” in the negative sense of the word “hacker”. It’s a way to convey to the reader the level of sophistication used in the attack by describing the hacker in this way.
It’s in the name, so it doesn’t seem worth disputing that at least at the time when the term was coined- it did have to do with age
> or even skill
Skill is literally the defining feature.
What exactly do you mean by “it’s simply a hacker term” anyway? Are words just sounds we make with our mouths?