In every thread like this, there's an argument like yours, taking the absolutist view that individual workers should have unlimited freedom ("completely and totally incapable," as you wrote) to sacrifice themselves for money. In the micro sense, you are possibly correct. However, as a society, we have decided at the macro level that no, workers are not free to make that decision because to do so would inherently drive the collective working environment to the bottom.

We make rules about a lot of things to protect the collective good at the sacrifice of the individual. Workers are not free to decide that climbing a tall tower without a safety harness so as to go faster and complete more jobs for more money is acceptable. Workers are not free to decide to put their unprotected hands into fast-moving machinery so as to be more efficient and complete more piecework for more money is acceptable. Workers are not free to decide to inhale toxic gases, labor in buildings without sanitary facilities, or be worked non-stop until the worker passes out from exhaustion. (These are, of course, generalities but, again, we as a society have also decided that carve-outs can exist where required but these are the exceptions to the wide rule.)

I would also note that the person to whom you replied expressed a favorable opinion of the trade-off for health against money not being made. No rule or law was proposed. That, too, is part of what society does: we debate things in good faith, not with the assumption that an opinion is a dictate by fiat. These rules are generally considered acceptable and good. It is up to you, the person with the view opposed to the current situation, to express why you disagree instead of simply turning the question back on the person commenting.