I think we haven't tested democracy variations quite far enough. I agree that the first-past-the-post model in capitalism has proven extremely vulnerable to mis/disinformation, and made it possible to benefit from the idiocy of your peers. But I don't think we've seen, say, RCV and proportional representation + robust finance laws prove nearly so bad.
Also, I think this take is disingenuous to the roots of democracy. It is a social technology used for legitimacy in tons of situations by many groups, for a variety of reasons. Often it is neither dumb nor a method of obvious control.