So my experience with moving from a Cambridge undergrad to an Edinburgh postgrad, albeit a couple of decades ago now, was the expectations between the two were nowhere comparable.

Cambridge if you'd not done the homework before the tutorial, you got sent packing for wasting everyone's time, but in Edinburgh it was common for all but the best students to only start the homework at the tutorial (thus wasting their opportunity to ask questions on trivial stuff they could get by reading the course notes.

Equally on exams, the minimum standard at Cambridge was "regurgitate proof from course notes" with the other 2/3rds of the marks for iterating on it with unseen material, whereas the Edinburgh exams the regurgitation would get you 100%.

Unless things have changed significantly (or Edinburgh is that much worth than other redbricks), I'm not sure I trust these rankings in terms of student quality.

Your anecdote doesn’t contradict the story - the University of Edinburgh doesn’t appear in the top 20 so apparently their “rankings” don’t think highly of the University of Edinburgh either.

(Also Edinburgh isn’t a redbrick, it was founded in 1583)

How very odd. In most of my finals at Exeter Uni. Physics department in the 1970s regurgitation of course notes got you nowhere because all the exams were open note so the examiners didn't bother asking questions of that kind. The Quantum Mechanics exam was an outstanding example, not only did it not ask for any regurgitation most of the questions required the student to provide answers to problems that had not been more than hinted at in the course.

This was also my observation but in the reverse direction. I turned down a place at Cambridge to do my undergrad at Edinburgh a few years ago (for various reasons, not relevant here). It was only the top n% of students in the cohort who'd turn up for tutorials (prepared, or indeed at all), do assignments without cheating, ask questions in lectures, etc. Getting high grades in exams was mostly a memorization game. There was a really high workload but that was more due to busywork than intellectual challenge.