You haven't considered the most important part of this: is stigma good at changing behaviours?

If you stigmatise something and shame people for it, you tend to push people underground. At that point rational discourse can't exist because there are social pressures to not reveal the unpopular opinion, and thus discussion doesn't occur.

It's foolish to think that people have stopped dying from stupidity, it happens every day in every country on earth. And it's foolish to think you can cure "the sin" of stupidity by using shame. This doesn't mean we ignore people's bad decisions, but that we must be realistic about the utility of our response.