Think the point is that at least for rock music scene, it was considered perfectly normal for underage groupies to get with rock stars.

Yeah it was illegal but so were drugs, and we know how famously sober the rock celebrities were of the age…

I think there was taboo unless everyone agreed the older man was “hot”. If they got with underage people because they were old creepy ugly dudes that couldn’t get with anyone any other way, absolutely taboo.

But if everyone thought they had a choice but happened to also include young women that seemed openly “partying” then people did likely shrug.