Why is Gen Z so insecure about their age?

I'm 27 and I feel young and vibrant like I did when I was 18 while there are literal 23 year olds who feel like they're 60. Then there is a whole thing about age gap relationships (platonic and romantic) and anybody above the age of 25 is a predator. I'm curious about why this is, like what happened in the past year to cause this insecurity and ageism throughs people in your own generation.