Trump administration orders US embassies to stop student visa interviews

What kinds of statistics can we watch that might illustrate the brain-drain from these policies, on various timelines?

Some of it is going to be people who don't even bother to apply anymore, because nobody wants to study in a place where you get arbitrarily black-bagged halfway through your degree by thugs filling an arbitrary quota.

I imagine there are also some students will be out there who really don't use public social media all that much, and the lack of activity will falsely be taken a sign of concealment...