To be fair, that's not really what's set people off here. It's not the fact that Blitswing doesn't look G1, he actually looks fairly G1 for the movie aedthetic, it's just that he looks like a completely different G1 character. Everyone feels a bit lead a stray, even people with the most casual interest in transformers thought it was Starscream. It'd be like if they made a new Bat man film and the trailer showed what looked like the Joker, and it was a very classic comic book looking Joker, and then they reveal later that it's actually suppose to be the Riddler. People'd be understandably confused and pissed.