But authors are necessarily a part of their environment. It is -- literally -- inescapable. The good Professor was directly involved in the first World War, and the second was at his doorstep. His aversion to modernity could have led to him simply denying a a conscious connection between those real world epics and those created by his own mind.
But the works themselves put doubt to his claim. If we take him only at his word, and stop there, then that is the end of it. But if we recognize the imperfect ways we self-assess, well...