I think a large part of the show's mission is to help kids learn how to build healthy relationships. The show has been called the most sex-positive show on television, but it goes so much further than that. The use of dance as a metaphor for physical intimacy means that regardless of age all viewers can understand the body-positive message. And it is important for children to have access to these kinds of role models.
In our modern world parents have to talk to their young kids about gender, sexuality, love, identity, and these are really hard subjects. This show frames all these issues in a context young children can understand. I don't think there's anything inappropriate about that.