Can You Objectively Assess Objectification? And If Not, How Can You Regulate It Objectively?

Today's decision by the UK's Advertising Standards Authority (ASA) to ban one out of three poster ads for Calvin Klein underwear on the basis that it objectifies women is somewhat mystifying. At least, it is to me.

Why? Because trying to be objective as possible, I can't see why any one of these ads is any better or worse than the other two in terms of objectification of women. So why not ban all of them? Or none of them? And given that there were only two complaints, they averaged less than one complaint per execution, so objectively speaking, why did the ASA even bother to investigate?

The complaints' concerns were that the imagery used in the three ads was overly sexualised, and that they were "offensive and irresponsible, because they objectified women", and "inappropriate for display in an untargeted medium", i.e. out-of-home poster billboard ads.