An overall disdain for anything too trendy or popular.
My teenage family members live and die by the trend cycle. Teenagers have always cared about what's cool, but now the trend cycle is so fast it's impossible to keep up without spending inordinate amounts of money and generating tons of waste. It also just doesn't seem great for their self-esteem.
I was a teen in the mid-2000s/early 2010s hipster Tumblr era, which of course came with its own issues. But at least the trend cycle took a few years, and if anything I liked was unpopular I could just roll my eyes and say it's just too obscure for you normies to understand.
I respectfully disagree. Yes crazies are getting crazier and louder, but overall more young people are trending left -- and further left -- than ever. I don't think bigotry is particularly cool or trendy to most teenagers.