I laugh, but you're totally right on the mindset. Whenever anyone asked "who will be a breakthrough artist in the States?" the answer was always "[hip hop-influenced group], Americans could never like a group like SNSD or Wonder Girls."
nobody sounds like twice in the us.
there is a big demand for fun, positive, high production value music - disney doesn't do this anymore.
being distinctive is a major plus in a crowded music market.
most importantly, broad distribution through target was a game changer.