Back when I worked at a convenience store they told me to card anyone who looked like they might be under 25 before selling cigarettes. I actually think it is entirely reasonable to expect an adult to engage in behaviour that would avoid this situation.
I do worry about age of consent laws where they potentially criminalize ordinary teen sexuality (e.g. where it is illegal for a 17-year-old to have sex with an 18-year-old). I also think that 20+ years in prison would be extremely draconian for the alleged crime. But in the land of draconian prison sentences, this case is never going to be a great example to highlight the problem of those sentences.
Somehow when I think of a 16-year-old prostitute, my sympathy immediate goes to the 16-year-old prostitute, rather than their “clients” (i.e. assaulters).