Yeah, most of those games are made for older people. A lot of them are made for older people with no taste. Only young and stupid kids like bland things, and most
overly-adult themes go over their head or don't interest them. Most adventure games these days are bland things, with adult themes.
It's true, and weird to think about, that very few things in the hype-o-meter (even Dreamfall) would appeal to me when I was 13ish. Maybe Vampyre Story, yeah.