IMHO doing obviously unethical work for money is also degrading and is much more common than porn. It's one thing if someone wants the money and doesn't care, but there are millions of people around the world in e.g. scam call centers that do this kind of work to stay out of the worst of the slums.
"fuck you money" is undefined. I am pretty sure that there are people that do not care about the amount, they care how they are compared to their peers. Just for these people, arguably most people, your solution already fails.
The other simplification is the assertion that degradation is a universal concept and that the threshold is the same. This is extremely difficult to define and i am pretty sure a catholic priest's definition of degradation starts at anything else than marital sex. We can define something more liberal but then we need to take the great step of saying what is acceptable regarding one's sexuality. Seems to me most liberal societies decide to bail that discussion, just deciding that if you did it without coercion it is fine. I also find that position objectionable by the way, as there are work contracts which are by definition illegal(eg, a contract for work of more than 40 hours per week), and i do not see why we could not go further.
All and all, maybe giving these people social security, requirements for mental and physical tests, a subsidy for change of employment, could help lower the chance of unfair and dysfunctional societies. At the same time if someone wants to do, distribute or consume this stuff, then we get the benefit that the chain is legitimate. I think that is really worth it. Sex workers do really important social work.
But agreed that the greater good would be looking at the structural facts that force people into unethical work and addressing those.
But in aggregate, this system creates a huge financial incentive to exploit anyone you can.
I'm all for regulation, if done in a non-puritanical, individual freedom-promoting way. People should be able to choose to be involved in producing porn. No one should feel forced into producing porn.
If we, as a society, aren't willing to ban porn (and I don't think we should), then we have a moral obligation to prevent workplace exploitation in its production via regulation, investigation, and social support resources.