I find regional, ethnic, gender, religious and national bias fucking embarrassing.
It's OK to take something you like and has obvious quality and maybe talk it up a little, so it's natural that someone from Liverpool might, I dunno, say Lee Mavers is one of the greatest songwriters ever.
But you'd have to be a total cunt to try and claim the same for Peter Hooton, or that John Bishop isn't anything other than a totally shit comedian, or whatever
It just makes you seem weak, a bit desperate and open to mockery. And also invalidates all of your opinions about everything else