Question for Sam about the issue of high-skill immigration: Does YC have any sort of tracking of the number of engineers blocked from going to YC companies beca

Question for Sam about the issue of high-skill immigration: Does YC have any sort of tracking of the number of engineers blocked from going to YC companies because they could not get a Visa? Could Sam write an essay with some anonymized examples of what happens when a skilled worker is prevent from working for a YC company? This kind of first-hand evidence can go a long way toward convincing other people of your point.