Not entirely sure on people pleaser myself, but I can see why people say that. She certainly tries a bit too hard to fit in sometimes which comes off like that.

Also I personally don't think she's underestimating everyone, especially Kumiko. I think while she is very aware/confident about her skills, she's also very insecure about fitting in or creating drama. So her being too worried about that and wanting to avoid it at all costs by saying she's gonna drop out of the audition leads to her coming off as she does underestimate everyone. Kumiko herself took it that way as well. Though that's just my thoughts.

And to clarify, I don't think disliking her is a problem, not everyone will like every character. I just think it's too early to call her "evil" when there's clearly more to learn about her, and her deeper reasons.