John Stuart Mill would say “I told you so.”  Support of free speech correlates with intelligence, as one would expect, because exposure to challenging ideas serves as good check on confirmation bias. The challenging ideas of others tend to cause us to reexamine our own beliefs.  Here are excerpts from “Freedom of Speech: A Right for Everybody, or Only for Like-Minded People?” by Jonas De keersmaecker:

[W]e sought to explore whether higher cognitive ability was associated with more principled positions on free speech. . . .  The series of studies suggest that cognitive ability is related to support for freedom of speech for groups across the ideological spectrum.  . . .  [I]ndividuals with higher cognitive ability are more appreciative of the free flow of divergent ideas by groups at various places on the ideological spectrum. Indeed, even when these groups voice ideas that they don’t like.