Meh, I have to admit they're not wrong. There are two things working in parallel here. Firstly the grading scale has a lot of headroom in the 80s and 90s to reward students who are genuinely a cut above not only their set, but perhaps every set in the last 5 years. The reason this doesn't have a separate classification is partly historical, but also that these students would hopefully go onto further study and reasearch: hence their individual module grades will be seen and are relevant. In certain subjects (definitely maths, as that is what I studied) it allows examiners to set really tricky parts of questions they don't expect most people to get, without condemning most students who don't need to know that when they go to work at Goldman Sachs or whatever. If companies really cared about delinating between a first and a high first, they'd ask for module grades, but evidently they don't.Love how all the Brits (I assume) get super defensive as soon as someone says something negative.
From what my friends told me who did study abroad it seems true that it is ridiculously easy to get good grades in the UK (they did business, English, law and economics).
But secondly, and this is one that you many actually take issue with, is that in prestigious institutions more or less pre-filter their students before they even reach the lecture halls. This means they assume any student they admit, provided they put in an appropriate amount of work (for me that was around 40 hrs p/w in term time) is capable of a 2:1. Hence, in final classification, they tend to give most students who have provided good enough evidence that they've done this work a 2:1. I would personally argue this isn't a problem by taking an argument from Bryan Caplan's "The Case Against Education" that employers, when they see a degree, care more about the fact you were intelligent enough to enter that institution and able to put up with enough tit to get through it than they ever would the actual content of that degree. This means that, while yes a 2:1 or a first may not indicate much about the suitability of a candidate for further research in this area, it does indicate that the student is both smart enough, and able to work enough to be employable.
We've definitely got a harder system than the USA, but I wouldn't necessarily pit our graduates in most areas against say, those of the Balkans or Korea. They all seem very good.