I frequently agree with you, but I can't on this topic. I don't know that commentators on so-called "liberal" networks use terms that have been vetted by the more highly-educated community, but that they attempt to use terms, period, that simply go out of their way to confer the least negative judgment. For a person who is truly homophobic, few alternatives to derogatory name calling may be acceptable. For most of us, there is the Overton Window between using older, probably more judgmental terms, than the newer, but less-familiar ones that seek to withhold judgment. It may not be that NPR producers wait for usage to become valid through educational organizations but that the highly educated tend to be less judgmental.