I have a medium-sized Doctor Who fanzine collection with titles from 1975 onwards, and looking at the early examples of fan fiction (never what I was most interested in, I have to say) the fans of a quarter-century and more ago would have for the most part been baffled by the whole shipping culture. In fact, ten years ago it was only on the fringe of fan discussion. The cultural shift has put a lot of old fans into shock, I think.