The issue here is that the idea of “100% consensual” is 100% unrealistic. If working as a prostitute is acceptable and pays 10x the average salary, living costs adjust in reaction, then what is consensual about this?
Allowing unhealthy or undesirable behaviors to be economically lucrative doesn’t make them ethically good. To me, the scenario is dystopian because it’s saying we are incapable of managing our own desires to the benefit of society, and instead must (economically) force young women into selling their bodies en masse. Instead of having healthy relationships as the baseline, we just choose the easy option.
Adding to that, prostitution is tied up with human trafficking and lots of other horrible things that have nothing to do with individuals choosing what to do with their bodies.