You can slate a lot of places if your experience was driving through the rough parts of the town/city, or you are basing it off of the very central run down high street areas that have not been reinvested in since the 80s/90s when people actually went to shops.
People diss my local town as being one of the worst in the area but that's because they reference the smack heads and wrong uns in the old town which has been in decline and dying for decades. There is now a big refurbishment finally to do it all up but it will always have that rep of being rough. In reality, there are loads of different areas in and around the town with differing housing types and ages, lots of new build estates going up.
Bracknell mentioned above is another one that used to be the same and thought of as a concrete jungle back in the 90s. Same as Basingstoke, Reading etc. A lot of these places have now had significant investment over the last 20 years with all new modern shopping complexes. There are loads of original estates around and yes some of them are older council ones, but there are also a load of new build stuff that has gone up recently and all sorts of ages of houses. It's usually exaggerated and from old reputations when someone tars an area with the brush of being rough in its entirety. Granted, there are still some, but I think people are a bit harsh with some of their claims. (Fully appreciate there are some places stuck in a time warp and very old and grotty).
Define rough. Run down? Old? Full of horrible people?
You could visit a lovely Welsh countryside small village just as an example, and claim the entire place was "rough" because the locals were "different" and protective of their area. It's all relative. Just saying.