I don't doubt he's in the 1% or 0.1% of candidates you're interviewing, but there is one very simple solution startups could apply to make it easier to find top talent -> remove "US ONLY" from their job listings.
Lol because foreigners aren't known for being scammers.
You might not be aware, but hiring outside of the country causes a whole slew of other points of friction and complexity. It actually isn't "one very simple solution" in practice, which is why many startups don't do it.