@clumsyduck
it's an illogical argument . Sure at an individual level you could advise someone they may have a better life out of London . But everyone can't move out of London
The argument reminds me of when people come on here fed up of being on a low income and people say " get a better job then " it's illogical as everyone can't be in high paying job same as everyone can't just up and leave London . It doesn't work like that
I agree with this.
And maybe people don't WANT to move out of London - or want to move IN. If everyone moved out (or didn't move in,) because they can't afford it, there would be no-one there. 
I quite like London as there is lots to do and lots of opportunities there, but I cannot fathom for the life of me why the homes are so crazy expensive. I mean multiple tens of millions for the most expensive ones. And over a million for a 'normal' home in an average area.
Why?!
It never used to be this way pre-1980's.....