London perfected ignoring everybody long before even the rise of mass circulation newspapers according to diaries of family who knew the place a hundred years ago. The Tube of the eighties celebrated the apotheosis of ignoring one another and the British seem to make a art form out of studious but "polite" asociability* in every queue.
Actually reading this discussion I've realized that I have seen almost nobody using headphones in London in recent years, eliminating possibly the highest barrier to interaction. Curiouser I have most recently only noticed people glued to their phones whilst walking not standing at the bus stop.
*as opposed to anti social manners for clarity