I remember being a teenager and intentionally dialing down my ambitions, because it was socially uncomfortable to have people's perceptions of me be tied to the things I excelled in.

Figured I had my whole life to have a job, so didn't really wanna do a startup or anything like that. Watched all the Macworld et. al. keynotes and knew all the specs of all the devices, until I got tired of being pigeonholed as "the computer kid."

This is an urgently dark pattern to avoid for parents, but I feel helpless as my own development was heckuv random

Not sure I follow, you were afraid of being a "nerd" and dialed your ambitions to try to be "cooler"?

"because it was socially uncomfortable to have people's perceptions of me be tied to the things I excelled in."

I think usually it's the other way around, or I'm not understanding this correctly. I was best at math in my class from grades 5 through 12 but never felt "awkward" because of it, rather I felt proud. Which is also wrong but I digress