I'm 26, a newlywed with no kids yet. But I went to my first quilting class with my mom when I was 12. Yup, it was me, mom, and all the grandmas so I understand where the stereotype comes from. Doesn't mean it's accurate all the time though! There are many many young quilters on this board and at my in-person quilting guild.
But more importantly, who cares anyway? A friend is a friend. A hobby is a hobby. I'm glad to do quilting and hang out with quilters regardless of ages 'cause it makes me happy.