Seems to me it's mostly Americans who find it "off putting"? I guess to them it's something exotic, where as us Europeans are more used to British accents?
I think it comes down to a mistaken belief in there being a "standard English" that has no accent; for Americans, it's an American newsreader accent and they don't seem to understand it simply sounds like a generic American accent to everyone else, not an
English one.
Obviously it's not
only Americans who do this. As a Geordie who spent some time living in Hertfordshire I never heard the end of how outrageous it was that I had an indecipherable provincial accent compared to their no-accent-at-all. It was quite amusing listening to them having the same argument with Cockneys who
also used the same argument, with everyone being largely incomprehensible to each other.
It's slightly tiring seeing all British accents described as "posh" and "snobby" though: I mean considering my PC is a rough-as-a-badger's-arse Cockney who I'm sure is about to yell "gercha!" at someone.