You are certainly welcome to your interpretation, but a couple of comments from a fellow rube:
The principal is certainly given plenty of detail and his own song. And he is representing a good chunk of the midwest that I know.
An unhappy teen being angry at the behavior of certain peers and adults and generalizing it to her entire state? That felt real, not mean-spirited. Especially when the plot turns prove to her that Indiana (and beyond) can support her and her freedoms by the end of the play.