In contrast many of us would have been told to "aim for a simpler project" if we proposed something like that to our computer science teachers.
it's mostly being born to a) rich parents who can afford to pay for extra-curricular activity, good schools or who have the time to "improve" their kids or b) being around schools or universities that can recognise the talent and give talented kids the input and resources they need. Both a) and b) are based on pure luck.
For an example, check out Bill Gates' early life: https://en.wikipedia.org/wiki/Bill_Gates#Early_life
Rich parents, exclusive school (with their own computer! unheard of at the time) and local companies that let Gates and other kids screw around on their computers. Luck!
I do think that without hard work/talent Bill Gates and all these other successful people wouldn't be where they are now, but without luck and the correct circumstances all the hard work in the world doesn't bring you anywhere, your genius won't help you.
Look at William S. Burroughs' life - an extremely talented writer from a rich family, who still "dropped out of society", later befriended Kerouac and Ginsberg who were the big factors (reasons?) in him becoming a great writer from age 40, without these people we wouldn't know the name; his genius wouldn't have helped him alone.
The term 'genius' bothers me too because it seems calling someone a genius is less about the object (ie the person we are talking about), but more about the speakers feelings toward that object (eg godlike awe etc).
Even without them I was building things like Enigma machines, games and such in QBasic.
This isn't about belittling this guys achievements, but realizing that with the free software movement and the internet in general the barrier of entry has dropped so much that stories like this are naturally going to become increasingly common.