Is your opinion about the latter because the self-taught may not stay on task?
As a self-taught person on a lot of different matters, I find myself exploring rabbit holes that expand my knowledge, but don't progress the task I originally started doing.
My reading is that the statement wasn't an opinion either way, rather it was questioning whether survivorship bias needs to be accounted for.
To your point though, I think it doesn't matter so long as you've learned to deliver business value. Application of broad and diverse skills may deliver value at a start-up for example, but wouldn't get too far at a ticket shop.
The point I was raising is that I don't think it's the self taught angle itself that is the causal factor. As an example, there's lots of things I'm self taught at but also terrible.
However, someone who already has the talent to be really good at something and who has the inner drive and motivation to push themselves is someone who is likely to excel. So if you find someone who is excellent at something and self taught, it's not a surprise. They probably combined natural talent with a strong work ethic, and lots of exploration of the entire search space.
As a self-taught person on a lot of different matters, I find myself exploring rabbit holes that expand my knowledge, but don't progress the task I originally started doing.