I don't know about that, places like central London and Manchester are quite densly populated, at least by UK standards. And the UK only really got into suburbs after WW2, when huge swathes of the urban population were moved into garden cities.
I live near Manchester, I know, but the city centre is still nowhere as dense (in terms of dwellings) as most towns and cities on the continent. It's changed for sure - lots of old warehouses and factories have turned into flats - but the city has clearly been built for business activity first and foremost. And as soon as you move to smaller towns, like Warrington, the number of people actually sleeping in the immediate town centre falls to almost zero. Brits just want to live in suburbia and in the countryside.
UK being an exception, sadly. Which is understandable, considering they basically invented the "suburb" concept and then exported it to the colonies.