I can't believe youngsters these days!

This past weekend I had one of the moments where you first think "Are you serious?" and then it is quickly followed by "Oh no...I'm getting older". The aforementioned moment occurred while I was waiting in checkout line at Target. I was daydreaming a bit (for some reason the lines were particularly long), when I snapped out of it I overheard a conversation going on behind me. I wasn't trying to eavesdrop, but what I heard blew my mind. It was a woman in her mid to late 20s and a girl who was probably in high school discussing a concert the girl's friends were talking about. She mentioned that her friends were going to a Metallica concert, and that's all they were talking about. I wasn't impressed as I've never really been a big Metallica fan, but then she uttered the words... "Who is Metallica anyway?"
...
Are you serious?
Like I said, I was never a huge fan, but I know who they are, I could sing you a few songs (hell, I can even play a few on Guitar Hero. It was then that things got worse. The woman's explanation was this: "They're a hard rock band, they were big back in the ninties"
...
Oh no... I'm getting older.
Not only are one of the most popular (and overexposed) hard rock bands of all time now a relic of the past, now the entire decade I was so familiar with (including my high school years) is being referenced as "the ninties" in the same tone that we used to refer to "the eighties".

Side note: before the response I thought to myself, "geez! even my mom knows who Metallica is!". In retrospect this did not help my case. :(