News is a product like any other. If the way anchors look and dress are correlated with the number of viewers and the station's bottom line, what are we supposed to do in a capitalist society? Pretend there is no value in aesthetics or provocative imagery?
I bet if programmers dressing provocatively was positively correlated with increased profits, we'd see some low-key encouragement on programmer attire.
I still think it's bullshit for women, but I can see a case for wanting sexy people in front of a camera. If looks didn't factor into anchors careers in any way whatsoever (for both men and women), I am willing to bet over half of current news anchors would never have become anchors in the first place.
However, I do think if stations want their anchors to be glorified models then they need to be upfront about it from the get-go so all people are aware of the requirements and stipulations of the careers/jobs they are pursuing.
Imagine if these standards were applied to men who are programmers. Instead we can dress however poorly we want, bad grooming is basically celebrated.