The problem is that most people get their understanding of the world through mass media, and video games are now bigger than film or TV combined. Like it or not, video games have an educative role. For instance, almost everything your average person believes about ancient Sparta or the Vikings is complete nonsense from cryptofascist films like 300 or weird liberal revisionism like the Vikings TV show. If the only WW2 games people can play are clean Wehrmacht denialist rubbish like CoH2, don't be surprised when the average understanding of the war is that the nazis weren't so bad.
For example, when I was around 7-10 years old I read a lot of (school) books about ancient rome and greece, but I still thought hoplites carried gigantic pikes and that Onagers were used on the battlefield because I had seen it in Rome Total War.
That was exactly my point when I said it might be either trivialized, twisted, or entirely spoiled, because of the fact it is such a powerful tool. Games are a mainstream vector of information nowadays. All the things you mentioned and how stupid those are depicted in the games are true (like greek states with the lightning of Zeus under one banner, or Macedonia from the very same total war game with a big Lambda letter on their banners...). Those are however ancient times and we basically talk about the rather modern history of mankind and cannot agree to one scenario (as humans). I fully agree games should be educative, but mind that perhaps yourself, myself, many people on this forum know or pursue to know the history of their countries, world history - can distinguish between the facts and fiction but there is still a majority of kids that will learn it solely from this medium. This is a real threat, in my opinion, to leave such important matters in the hands of game developing companies. History has to be
thought taught but imagine tools as powerful as games used in the wrong way.
Germany is a very good example of how modern history teaching can be altered. One would say the history of the holocaust should be taught to young germans (IMO in literally all countries) - no brainer. In primary, secondary, high school. So we are all sure it won't happen again, right? I was once in the museum in Cracow and there was a part of the exhibition dedicated to the restoration of the building. One guy from a German school trip (around 15-18 y.o.) asked why it was so massively destroyed. Their native tour guide said that nazis bombed it. It sounded like those guys (Nazis) came from some gloomy place in space and smashed half of Europe. The old lady who listened to that interrupted him and explained that those were his ancestors who did it. This guy was shocked, didn't know what to say. He simply didn't know. I have seen many similar situations like this. Germany as a state filter the history, probably to ease the emotional burden for their young generations. Have you ever heard about concentration camps in modern-day France and Austria? Not as many as what is modern-day Poland but shortly after the war those were razed to the ground - no place, no problem. They do not teach about both the fact those camps were there and the fact they wanted to hide it in the first place. So all in all that is why I am afraid and reluctant to see next generations being taught history by the videogame industry (without supervision - like there is any nowadays).
I really believe that old-school history classes would do. The problem with
them those classes are... sometimes teachers (from my example) and that they stopped in the early '70s with their teaching skills. Anyways, this all may sound overrated but there is nothing better than people discussing those things and asking questions. The more international group will work on it the better.
P.S. Must add that I met Germans who know their history very well and really don't want to generalize - I see that there is still hope.