I would take your point on stress but the CEO of the company I worked for was, in some ways, extremely forward thinking and all applicants were called in at 0900 and the maths test was given as "take all the time you need, you have until lunch, 12:30 to complete the test", 40 problems.
I have read of comments by various Professors of Mathematics at various Universities lamenting the state of up to Sixth Form maths, but this has only happened since my retirement and, as I have said, my recent experiences do not exactly fill me with hope of much significant improvement. If it happens I will be only too glad to see it - old stats freak me!