I think law would be rather dry to study just out of interest of you had no inclination to pursue a career in it. I am presuming most people who embark on a law degree harbour ambitions to be a lawyer in much the same way as people studying medicine harbour ambitions to be doctors.
It seems like there a r e law degrees where entry to the legal profession is overly ambitious and I think this does not serve students well. However there will be graduates of more 'middling' universities that should perhaps have that chance of a career but in order to have firms gain confidence in a particular degree the university must demonstrate serious intent.
I take @Xenia point that ultimately professional exams are the litmus test for a legal career and in reality there probably is a reasonably strong correlation between university rank and scores in these exams. This is not to say that only students from a very small subset of universities will be able pass them and the university blind system could have a role here?
On a side note looking at the Oxbridge entrance thread I become increasingly of the opinion that there is something imperfect in a system where we have a 1 in 5 application success rate from amongst the brightest pupils in the country. The process seems absolutely brutal.
One feature I have noticed of RG (non Oxbridge unis) is that courses have to cater for those ranging from narrowly missing out on Oxbridge (often with immaculate grade profiles) to those that have gained entrance through clearing and this can be challenging.
You either have those at the bottom struggling and in real danger of getting a 2:2 or those at the top funding the rigour not adequate and feeling short
changed.
It seems that theoretically we should have Level 1 degrees (Oxbridge and a select number of elite courses at other universities to accommodate those of Oxbridge aspirant level), Level 2 degrees that would take up a significant proportion of RG courses then Level 3 taking in the rest.
All this is obviously hypothetical (and maybe counter intuitive to my previous posts) but the make or break Oxbridge application route seems not the best way to set up an education system.