David Duchovny fears conspiracy theories that packed ‘The X-Files’ are now a mainstream way of thinking. The 63-year-old, who was watched by audiences of up to 30 million playing FBI alien-hunter Fox Mulder at the peak of the 1990s sci fi series; popularity, said his character’s obsessions with government and establishment cover-ups was “fringe” at the time it was shot, but have now become normality for swathes of society. He told The Times: “Mulder’s way of looking at the world was through conspiracy and that was the fringe at that point. “It doesn’t seem to be so fringe any more. It’s really…