I always thought the original 6 Redbrick Universities were usually considered to be respectable institutions for people who are high achieving, and/or for people who didn't get into Oxbridge. I always perceived them as being big brand names in academia, having existed as universities for a long time and having lots of history attached to them. They also tend to do excellently in Global League Tables - which, although might not be perfect measures of 'academic excellence', they do tend to rate universities which people have 'heard about' very highly. I know that doesn't indicate 'reputation', but I would've thought this is a good securer of long-term reputation because at least they remain globally recognised, as opposed to certain universities which go through phases where they suddenly shoot up the UK rankings and become the 'next best alternative to Oxbridge', but don't necessarily stay that way.
I went to one of these original civic Redbricks, most people I met there were clever/well educated, an awful lot seemed to had come from grammar/private schools, and quite a lot were Oxbridge rejects. The student body was almost exclusively middle-class/new money. In other words, I gathered it was a pretty sought-after institution, and I'm very proud to have gone there, considering I went to an ordinary comp and had personal problems which affected my studies.
So why does TSR tend to put these universities down, and put so much more emphasis on UCL/Durham/St Andrews, and even 60s universities like Warwick/Bath/Exeter/York? Is it partly because of the fact that (Bristol aside) they're in big cities which are often perceived as being 'rough', whereas the others are in nice touristy towns? How does location infer 'academic reputation'?