My son liked to dress as Ariel when he was two. He also enjoyed ballet until changing to street dance aged 5 (probably due to peer pressure) and still will happily play with dolls and his sisters girly shit when they're all together. He puts on rather a butch persona when at school, but his prized possession is a box of shiny silk bow ties. This is who he is. A mixed bag..... A boy who has interesting personality quirks.
My older daughter has always hated pink, likes her hair short and space/dinosaur themed things. She is dreamy, poetic and looks forward to being a mother, but to look at her, you'd think she was a boy.
My middle daughter is incredibly sporty, she hangs with the boys, she plays football, she likes trains and playing the drums. She has a pink feather boa draped over princess bed sheets at home, her inner sanctum is super girly.
When did we stop allowing children to be complicated. Bullies are stopped by firm action from adults, or removing yourself from a situation, not by changing yourself to make them happy.
I consider it unlikely that three young people who were friends would all have a diagnoses of gender dysphoria without external pressures denying them agency to simply be GN.