i've had provisions put in place all through uni because i have long-term anxiety. they gave me extra time in exams, a use of a laptop for exams (because i have shaky hands from anxiety), longer book loans because i'm a slow reader, they don't ask me questions in seminars because i might panic from the attention. but i wouldn't go so far as i can't write the final exam at all. if i can't write the final exam at all, i shouldn't be at university.
as far as uni applications, yes i think it should be considered in terms of past performance. but not in the sense that unis should ignore the fact an applicant may not be fit to study the degree. the fact is, it's more responsible to reject an applicant if they are unfit than to take their money and watch them fail.