I think there's a double typical mind fallacy here. You were surprised because your mind doesn't work their way, and it doesn't occur to them to do anything about it because they just think that's what tests feel like. Also, an anxiety disorder is tantamount to a mild mental illness, and people still have a lot of hangups about seeking mental health services in general.
Yeah, I think you're right because when when people say they get nervous before tests, I think, "Oh sure, I get nervous too!" But not to the point where I spend half the time sitting there, unable to write anything down.
I'm a bit concerned that a lot of the treatment options on that page are drugs. Is it really safe to drug people before their brain is supposed to do mathy things? Is it cheating? Do any of the people you know have any handy CBT-style rituals that help calm them down? I think from now on I'm also going to persuade professors to call exams "quizzes" or something.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.