I think people in the north like to cling to a whole load of silly myths about London. The one I hate the most is 'it's unfriendly'. I'm a Londoner by birth, and have lived there on and off - though I'm currently based in the north. I regularly hear this complaint about unfriendliness. Yet the city I live in is one of the rudest and most unwelcoming places I've ever been - far, far worse than anywhere in the capital! It's like there is some kind of mass delusion here that grumpiness and sometimes outright rudeness are somehow manifestations of bon homie.
(My pet theory is that people from elsewhere turn up in the capital and don't know how anything 'works' (the tube, for example), feel inadequate and surrounded by people 'in the know', and then characterise it as unfriendly to compensate).
However, I would also say that Londoners have a lot of myths about the north too. Some of them are really quite patronising - that it's backward, that people are stupid, that it's not 'go-getting', that it's 'like going back to the 1970s'. These are equally wrong, and equally offensive. You hear it a lot around the move of the BBC to Salford, and sometimes from surprising people you wouldn't associate with such snobbery.
Like many others, I moved to the north so that I could spend time doing what I really wanted to do with my life - it's not getting 'in the way' of my experiencing culture, it's actually the thing that enables me not to work and to pursue my artistic dreams instead. I could never have afforded to do this in London. The north has been amazing to me, and I'm grateful to my city - rude as it is - for letting me have this life.