Note to Treyarch:
If you're also going back to WWII next year here's what you do for World at War 2 to make it distinct from what we've seen before. Have it set in the Philippines and you play as a native Filipino who witnesses the Japanese invasion first hand and joins the resistance. Wrap it up with the battle to retake the city of Manila, which was almost Stalingrad level in terms of scale, carnage and craziness. Maybe alternate it with one of the all Japanese American infantry units who served with extreme distinction in it the Italian Campaign. Wrap that up with the Siege of Anzio which is another epic and bloody battle that a lot of people have never heard of. Hell, maybe even have us play as a Chinese soldier fighting the Japanese as well. Would certainly appeal to the China market.
Okay, here's why that's never going to happen:
1. Storming the beaches of Normandy is the the go-to because everyone knows about it. It's seen as the turning point of the war, and it's one of the aspects of the war that is most talked about. Hence everyone goes to it, because it's the aspect everyone knows about. I mean the entire history of WW2 is never explained in schools, it mostly summarized with bulletpoints. Hitler comes into power, he starts to overreach his barriers, he captures Poland and France, he bombs Britain a lot, Pearl Harbor happens and America joins the war, the Holocaust happens, D-Day happens, Hitler kills himself when the German forces are failing, we drop nukes on Japan, end of war. That's all people really know about, or care about.
2. Again with Normandy, there's another reason why they go with that one: you're fighting Nazis. And as Brad Pitt once said in a certain movie, there's nothing wrong with killing Nazis, because they ain't got humanity. In other words, you have very clear black and white villains to fight if you fight against Germans during WW2. The same can't be said about Japanese forces who were just part of the Axis Powers. Yes, they did very inhuman things to the Chinese, but for the most part, Nazis are seen as the true monster of that war.
3. While yes, it might be a popular game in China if you're playing Chinese soldiers (because playing white American soldiers mowing down the Japanese will harken back to old school era racism of that time), you'll be alienating another demographic, the Japanese. Yeah, WW2 games don't sell very well in Germany, because why would Germans want to play games where they are killing their grandfathers? The same would go with a WW2 game where you're killing the Japanese. Not a smart move to alienate the second biggest video gaming market in the world.
In other words, sorry if you want the games to focus on a lesser known part of the war, but WW2 is always going to focus more on the black and white issues of the time. Nazis = bad, D-Day = good. This is also the same reason why the Wonder Woman movie is taking place during WW1, due to there not being a clear cut bad guy during that war, but Nazis were clearly the bad guys of WW2. This way, Diana sees the world outside of her Paradise Island as shades of grey, and she's not sure of her place in this outside world. Again, while the Japanese weren't saints during the war (but then again, no country is really saintly during wartime), they pale in comparison to Nazis, hence they will always be the go-to villains.