This never would have flown at my dance studio. I think for me, the problem is just the total package. The moves were not appropriate, but one or two on their own would not have been as bad. The costumes were too much, but in a different dance would not have stood out as muc .
Yes, when I danced I wore costumes that did not cover much more- but our costumes did not look like something out of a lingerie catalogue. My problem isn't just with how revealing (and we certainly had more conservative costumes when we were that age), it's the idea that they look like undergarments you would wear on a honeymoon.
We also would not have been doing so much thrusting, shaking, butt dropping, etc. Way too inappropriate for that age. The girls have wonderful technical skills. I don't know many girls who could do a triple pirouette. But it's hidden in all the nonsense. It takes zero dance training to do some of those shimmies, anybody who has been to a school dance could tell you that. That routine have showcased their skills so much better. Instead, there were a few complicated moves hidden underneath a lot of silliness.