Beyond fighting a Fabian struggle in favor of critical thinking and quality information flows (which are lacking all across our society, even if that lack is particularly obvious with a certain political group) I'm by no means certain what a good, useful, and just response ought to be.
I am confident that the danger is real and needs to be acknowledged. We need to find paths forward if we're to have any hope of keeping our civilization. And that means talking (and doing something) about the "propaganda, misinformation, and outright lies". Sticking our heads in the sand and screaming "Free Speech!" while the tidal wave informational sewage rolls over us isn't going to be sufficient.