Because this kid obviously has drive, ambition, and talent. Caring enough about his dream to put together a site and posting it to HN demonstrates that he's paying attention and he wants to connect with other driven people. Also that he spent 4 days on it when he could have been out partying shows a good deal more vision than a lot of 19-year olds.
He also is willing to make sacrifices and go halfway across the globe to join a team. Doubt you'll see his manager worrying if he's spending too much time on reddit.
It's also a big deal to leave your country and go somewhere where you have little base.
So in a nutshell, because he has the classic immigrants ambition, and won't rest on his laurels like perhaps someone who was born here would.
Talent and effort should have more value than a degree. Sure it takes some effort to get a degree, but with designers the portfolio should be far more important.