I’ve said for years that offhandly claiming someone is stupid trivializes the damage certain people can do.

It is easy to call someone stupid and write them off, because they’re stupid. It comes with the unspoken rule that you think they’re stupid and not worth thinking about.

Which is exactly what someone like Shapiro wants. The less you think it’s important to counter his claims, the more damage he does. You can apply this to most conservatives.