Correction: the politicians are accused of acting Amorally. Of taking action regardless of the consequences, of just not caring about the predicted real life effects, or the observed real life effects of legislation. That they're in it purely for their own interests, which have nothing to do with the victims. That they couldn't care less if the legislation helps anyone, just what it will do for them.

They're not accused of acting Immorally, which would be taking action with mal intent. They're not trying to increase child prostitution. They're not trying to enable it. They're not looking to abuse children themselves.

They're accused of being psychopaths, not criminals.

I don't understand how the default position can be anything but that politicians indeed act amorally. There is a very long history of politicians enacting laws specifically to hide prostitution, not to stop it. There is an equally long history of people asking them to do so. Society definitely wants prostitution. Society also wants very vulnerable prostitutes, well hidden from view.