Going the other way around is interesting too. If you look at how early many of them started working hard it doesn't quite seem as random. Say, Taylor Swift, by the time she was 12 or 13 it was pretty apparent she was dead set on making it in the music industry. And no, she didn't hit it right-off, did plenty of not-so-notable work for a while.
Just an FYI on Taylor Swift, she is not an "aww shucks" country music girl that cut her teeth by playing at malls and smaller venues. Her wealthy father purchase part of a record label which then signed her. The image that is portrayed is propaganda.
It's like the "Bill Gate's mom was on the board of IBM, so he's a phony" story. Just as in tech, successful people in other industries tend to have supportive parents.
The difference is that far, far fewer people have a moderately successful entertainment career compared to the many people who have successful software development careers.
With startups the distribution would be less like software developers but still not as extreme in terms of outcome as for entertainment. Ff you have a company that you sell for 5M or whatever that you own a quarter of you've done very well by normal standards but barely feature in value with the huge tech companies.
It's also common for people to write pop stars like Lady Gaga off as no-talent hacks who are totally run by their handlers, which is of course nonsense.
It’s funny that we understand this hit-based reality for music, tv, movie, and sports stars, but can’t seem to grasp it when it comes to startups.