I think we've seen time and time again that self-regulation of the industry doesn't work and that businesses will gladly fuck over society if they can get away with it and make more money. Usually that behavior is even defended with saying "Well, it's not their responsibility to solve society's issues. They are there to make money."
Barring nationalization of an industry, heavy regulation and/or taxation/subsidizing are the only ways to reliably protect the interests of society. If some businesses get killed in the process, so be it.
The problem with this attitude is that the rest of the world often doesn’t have these strict regulations and as result, businesses aren’t killed but just leaving the country.
Option 1: “we won’t trade humans as slaves at all costs, even if it makes us less competitive in the global market - and we don’t hold that conviction about other things”
Option 2: “We won’t trade slaves - and if we find you trading slaves we will kill you. So we don’t have to worry about competing against slaves in the global marketplace.”
Option 3: “slavery is less efficient than having the same people as market participants - so I don’t consider giving up slaves to be less competitive”
Many more options, and mixtures of any or all of them.