Well, show me a product of culture that doesn’t change things to tell it’s story. Private James Ryan only took inspiration from the Sole Survivor Policy, the rest is just invented for dramatic purposes. It is the atmosphere that sets the stages and creates the relevance of this film.
Games always struggled with telling stories and if you look at the CoD franchise, these stories are just as unbelievable. Yeah there might be a historic background, but telling that in a meaningful way, both immersive and exciting is a rather large task.