In holland they did make it legal AND taxable. The prostitutes for instance can become a one person business. Or they can join a Co Operation of these services.
They also have a Union, indeed the sex workers have a union...
They have access to regular checkups and their working conditions are kept an eye on. And only LEGAL girls and boys can become prostitutes.
What does this all mean it is legal it is made to be safe and hey it offers people seeking sex a safe place to have sex. Seriously

And if illegal things happen the police can go in and deal with it. It is taken out of the shadows and made into a regular business.
Less problems to obviously...
Really keeping some basic things illegal means they still will happen anyway. But much less safe, much less secure much less anything decent. You might disagree with what they do but they serve a purpose! Legalize it and make it controllable!