I've been to the US and there's no passport control whatsoever when you leave. You don't ever see a border guard on your way out — you go through security at the airport and then straight to the gate.
The real problem is that they now require social media handles on the visa application.
They had to stop at the border, and take the next flight back home?
(But what would happen, if one didn't disclose one's social media accounts and other things, when leaving the US)