People defend demands differently after you ask what problem the demand solves.

Demands defended in the abstract can be held indefinitely. Asked what problem it solves, it either produces a real answer, which gives you something to work with, or it becomes visibly arbitrary, which changes how firmly the person holds it. The question is not aggressive; it is genuinely curious, and that is what makes it effective. People find it hard to defend a requirement they cannot explain.

Ask what a demand is protecting against, in a tone that is actually interested. Then solve that instead of arguing about the demand. Many positions dissolve the moment their purpose is stated out loud.