Anyhoo the centre has very much dolled up now and prettified - from as you mention the bleak blackscapes of centuries of coal grime that was extant into the 80s - but to the point it's driven out much local life. It's becoming too manicured imo. When they cleaned up St Pauls Cathedral (a painstaking 20 year process) to reveal the gleaming cream stone the heritage societies were up in arms that they'd wiped off centuries of history and the 'beautiful' smoky colour of times.
This is a better example. The originally yellow bricks have been stained black by the soot, but kept that way. In other neighbourhoods they would have been cleaned or painted white or stucco'd over by now, but here they just repainted the bottoms and lintels to offset it, and make the history part of the visual fabric:
ttps://upload.wikimedia.org
I think in short London is very pluralistic in ethos, very interesting - almost too much sometimes. But it's not ugly.