How do people respond to the claims? I acknowledge that any response other than just "that's false" de-emphasizes the falsity of it, but if the response is "That's a lie and illegal," that's a different sort of thing to say than "That's classist," or the like for other claims. If people respond with "The powerful Jews will lock you up for saying such a thing, by the way I think it's 15% likely true," then that's an interesting case too, one that isn't a counterexample.

In one sense legal coercion is at the far end of a single scale from mild disapproval to ostracization to illegalization,but in another sense it is qualitatively different. A country within which saying something is illegal might have most endorse the illegal idea, or most oppose it by simply calling it "false", or most oppose it by emphasizing its illegality and somewhat mentioning its illegality, etc., or no majority of any type. What's important here is the social climate around the statements, for which the laws on the books are important evidence but alone don't make an example or counterexample of a country.