@allyeeee Yeah, I've found that too, and I'd believe that more too….
Few also argue against that, but not me. I've yet to be certain by myself though.
Anyways, magazines that mostly publish "Shoujo-Ais", are "demographically" bounded, you guess what follows that….
Yuri also tends to be more of mature…. (or ecchi to adult, etc.) I believe there is a distinction around this.
We follow genre systems like Baka-Updates Manga's anyway.