Another of many (all of them) fan concept arts which looks so much better than the amorphic lizards that passed all levels of approval at Blizzard before making it to announcement.
I don't think they can't make them look cool and intimidating and respectable, but they don't want to, it's not their design direction. They want to appeal to a certain crowd, knowing well their tastes and interests in the market. It's just not us.