The Older I get the Less I Can Stand Teenagers!
Teaching high school has made me much more tolerant of teenagers.
I don't see much difference in the attitudes from the time I was in high school - 15 years ago - and the students I am teaching there now.
All of my friends, though, who don't have contact with teenagers on a daily basis, are much less patient with them and their attitudes do reflect a certain curmudgeoness.
The vast majority of teenagers are not byproducts of the vile minority that most people think of when they hear the word "ZOMG TEENAGERS!"