"... but I have to get a job at a big company to sponsor my visa."
They're brilliant, motivated, and capable, but almost none are citizens. To start new companies they have to leave the U.S. To stay they have to work for a big company even though more than half are continuing their entrepreneurial class projects after the course ended. There are options to jump through difficult hoops, but those options are much harder for most.
So we motivate potential entrepreneurs to start elsewhere or give up their plans. What if instead we motivated the world to start companies here instead of elsewhere?
(Incidentally, we're organizing an event in October for non-U.S.-citizens who found ways to start companies and stay here to help inspire others to find ways to do it. If you're interested, especially if you know non-citizens who found ways to stay and live near NYC, please contact me -- http://joshuaspodek.com/contactconnect.)