This isn't really an opt-out right; surely there are people who would "consent" to situations of slavery or apartheid. This doesn't mean we should make those things legal.
If you want to disambiguate it from sex, consider whether someone should be able to sell (and thus another person to buy) an organ.
Then consider that the demand for purchasing sex massively outstrips the demand for purchasing organs.
Selling sex doesn't imply the loss of anything.
Literally thousands upon thousands of current and former prostitutes disagree.
The solution is not to make sex work illegal, or to make seeking it illegal. It's to help the people who don't want to be performing sex work. It's to give them food, and shelter, and training to re-enter the job market. But that's expensive, and it's difficult to explain to people with Christian moralities about sex why you'd allow people to perform sex work if they wanted to.
Which rights does consensual sex work curtail?