What's the evidence it's sudden? Everyone cites a single study by Lisa Littman. She didn't ask any trans children. Just their parents. And she selected for parents who didn't accept their children coming out as trans. Children don't tell their parents everything. And parents don't hear things they don't want to sometimes.
Imagine you're afraid to do something. Someone else does it. Nothing too bad happens. Wouldn't it encourage you?
Let me help,
Someone gets into a new school, he finds someone relatable that someone introduces him to a group of people who faces the same or similar issues like he does.
They grow up and when financially independent go through surgeries, hormone therapy etc. and come out as LGBTQ.
Should this be questionable?
If yes then, How do the majority of kids who are interested in programming/computers become software engineers? should be too.
Has everyone forgotten famous hacker Sophie Wilson?