Need to take into account how belief and human brains work. Once human brains become locked on to something ideologically, similar to religion, its not the quality of the evidence or argument that changes minds. To an extent we're designed this way to keep the world moving, as the natural order of things is relatively indifferent to suffering. You can indeed flood segments of the world with disinformation, and by the time you move to refute it, its roots are set and actions in motion.

I don't really know what the best approach is to it, but I don't think a simple hands off, engage with the argument as such, is a winning strategy. I don't really like the alternatives any better.