Post war, british town planning was more engaged with the ideals of modernism than other countries in Europe. Part of that was the view that the motor car, and road transport, was the future. So, many British cities were quite radically rebuilt, with wider streets, motorways, ring roads etc and the larger scale buildings that tend to go with them. Big shopping centres with big car parks. We tore up stuff like tram systems where many European cities rebuilt those transport systems as well as the old buildings and compact patterns of narrow streets they fitted in between.
There's lots about modernism and modern architecture I like - but unfortunately at that period the town planning that went along with it had very misconcieved ideas about transport, and it's those ideas that really screwed up so many town centres in the uk. The transport related decisons don't tend to get so much of the blame - instead people note the style of architecture, and associate that with some of the environments, horrible for pedestrians, that were created.
Southampton is a pretty good example of this.
It's true that many german cities rebuilt some of the war damage as historical replica of what was there before, although that mostly happened in the centres only. There are also plenty of german cities that did some rebuilding a bit like what happened in the UK, and they made some of the same mistakes in places. What's not uncommon to see in german towns though, are areas which were quite comprehensively rebuilt, with new buildings, but fairly much following the old street patterns. These areas don't feel so "post-war" in the british sense, because the basic form and scale of the older, more human friendly streets is still there. But the buildings themselves are largely built in a very plain and often functional style; they aren't all built in a psuedo historical style.