Ehh yes some people do make big changes to their career later on (even in late life), but if anyone is interested in pursuing a QUANTITATIVE subject, it is rather ridiculous imo that maths isn't a prereq. Yes, there should be other pathways through which people without 2u maths but with new-found passion for whatever area they want to do would be able to enter the degrees, but I don't see the problem behind making 2u a prereq for ordinary school-leaver entry spots. As long as there are other paths open (though probably going to be a longer path), I would think the need to promote STEM skills is a good reason for introducing this prereq.