As someone who grew up in and currently lives in white, rural America....while he's definitely not wrong, he's also generalizing a great deal. He's talking about a specific segment of rural, white America. A very fundamentalist one. As to the OP's question, it hasn't been the "true face of America" since before the 1950's, when the interstate highways and the postwar boom grew the suburbs and took people away from the farms en masse. In fact I'd argue you have to go back further, to the 1910's and 20's, for this to accurately describe what the majority of America was.
It's a portion of America just like everyone else is. Subject to its own delusions and inflexibilities. Just as much as hipsters and SJWs are subject to theirs.