They want to book her like Bryan because they don't understand Bryan got over in spite of their booking, not because of it.
Zayn has the same problem.
Sure, and a lot of that comes down to look. Bryan wasn't just short, he was bearded and scruffy and not a monster. He didnt have an impressive physique so Vince can't see way anyone would rally behind him despite his tremendous likability and understated charisma. They boiled it down to a chant and nothing more. Bayley looks like an average girl, they can't understand why fans, especially young girls would rally behind her, so lets make her look out of place and socially inept. Zayn is just DB 2.0, same thing.