I agree that worker protections need some work in the US, but to say that a black market brothel is somehow going to be safer than a regulated, above board one

I agree that worker protections need some work in the US, but to say that a black market brothel is somehow going to be safer than a regulated, above board one is simply madness. There is no way on Earth that sex workers are better off not having access to law enforcement. And that's just one facet of being in the black market.