The little I've seen of this show, and Taylor, makes me think that some very misguided adult has encouraged her rude, self-entitled behaviour in the name of making her "assertive" and "confident". It's not bad-mouthing a child to honestly assess their behaviour, and her behaviour is reprehensible...not to mention sad, because it will not serve her well as she matures into an adult.
I don't like to use the term "bitch" in regards to a child or their behaviour, and anyway, Taylor is neither a bitch nor bitchy. She is a child who apparently has lacked discipline and guidance. There are light-years between demure/submissive and "bitch". Successful, confident women find the balance. Taylor has plenty of time to learn, and hopefully someone will take it in hand to teach it to her.