I think you're more likely to meet younger people who identify openly as aro.
Also I wouldn't be surprised if that stat was slightly higher, since its still a nieche label that not many people know about, stats like these also change depending on methodology.
No shit though, I was at a Drama event thing and I was randomly put in a group with 2 other people, [we're teenagers] and we were talking about random stuff during a break and we both found out we all happened to be aro [and also, unrelated, both really liked The Owl House], it was very surprising!
Also one of my childhood friends that I've had for 10+ years is AroAce! and I think another friend of mine might identify as demiromantic?