You're taking the analogy in the wrong direction. The point is that the person who is trying to stop eating is obsessed with food, not that "people who eat three times a day are never obsessed with food". The point is that sex is a part of life, and trying to stifle pornography and prostitution is as misguided and counterproductive as trying to stop eating.
> Prostitution and pornography are also markers for human trafficking.
And why is that? Because it's illegal and unregulated. You're accidentally making a circular argument here: it's illegal, therefore the actors in the industry tend to be Bad People, so they contribute to the degradation of society, therefore it should be illegal? Look at Prohibition, or the legalization of marijuana in the US. It's not the thing itself that leads to degradation, it's the unwillingness to be mature about it.