There's a difference between censorship/bubble building and selection of intake, the latter of which is something we are forced to do constantly. There's a reason I don't watch Fox News (although I feel some basic awareness of what they and other propagators of half-baked polarizing sophistry are doing to our culture is morally obligatory to the responsible citizen), and it's the same reason I don't hang out in sports bars, attend promotional events for Scientology, join the local Objectivist club, or do a great many other things: namely, that I am forced to choose which elements will constitute my environment, and which voices will determine the focal point and efficacy of all my cognitive energy, which in turn creates the quality of my experience and allows for some discoveries/convictions, while probably preventing others. It is my path, and even not to decide it is, thank you Rush, to decide it.

In short, I think there's never a thing wrong with muting a nasty, bull-headed blatherer. The only question for me is whether a given interaction offers any possibility for a real, honest and open exchange of ideas, and if it does, whether that merits the energy the exchange requires.