it depends what's most beneficial: having a few percents of very mathematically experts people in maths-heavy professions? Or having everyone somewhat decent at maths, even when it doesn't affect their productivity in their jobs?
I don't have any hard data about this, but instinctively I'd bet on the former: I'd rather have a few hundreds more Sutskevers, than most of the country's bakers know their way around PDE.
Heck, he attended a correspondence college for 2 years (Open University of Israel) before his family immigrated to Canada and then attended UToronto (an amazing university, but not significantly selective by any means).
Ilya is by definition an example of why heavily stratified systems are subpar for human capital development - they remove the opportunity to identify talent from a broad pool, because humans can change.
And as I pointed out from personal experience, the difference in outcomes between IMO and non-IMO participants when I studied CS at HYS was nonexistent - we all did equally well professionally as well as academically. The difference was we all had the ability to study and get guidance from the same professors if we so chose.
A rising tide raises all ships.
And alternative explanation is that he's really nothing special. There are literally dozens of people like him in my social circle. Heck, my very spouse has a more impressive school record. The difference could be connections. He lucked out with his circle and a field of study.
> The difference could be connections
In Ilya's case, not really. He was an immigrant twice (first USSR to Israel, then Israel to Canada), and wouldn't have been able to do an MS/PhD at UT without actually being capable - it's not difficult to enter UToronto, but it's difficult to leave with a CS bachelors degree.
I've always felt a broad access system like the Warren-era UCs along with LBJ's "Great Deal" is of better benefit for a country than investing in building isolated ivory towers for education, because we have the ability to better ourselves, and that door should always remain open.