That's one hell of a sweeping statement. It might be grim in Salford but I live in the North-West and it isn't grim here. I'm from the South originally and there are some pretty dire places in respect of lack of culture down there. So let's not generalise please, it can cause offence.
Oh. I read it as Peter Grimes writing from in or near Salford and being mildly self-deprecatory out of frustration with his own fellow locals. Just goes to show, I suppose!
(And I'm from Oldham, but have lived down South for 10 years now.)