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You know those games are like 4-5 years old Single player games right?(Steam is very prominently multi-player driven) God of War had also sold 20m copies before it even came to PC, probably more people already bought it than every single Xbox game you listed across Xbox and PC.
You also conveniently missed out the Xbox games that have poorer numbers like Forza Motorsport(470 players right now) and Hi-Fi Rush(256 players). Those were big day one games only released this year. Those games being on PC should have no effect on Xbox sales as basically no one bought them.
Player count doesn’t equate to sales either. God of war has sold 3.27m on steam according to PlayTracker. Horizon Zero Dawn is 3.79m etc.(Flight Sim might have more people playing now but it’s only sold 677.1k copies) Gears 5 which is a major AAA Xbox game of similar age(but released day one on PC) has only sold 1.26m copies for example. Forza Motorsport is 62.5k sales btw. Even Days Gone has sold 2.64m copies on steam. What exactly would you expect from years old ports of single player games?
Another thing you should do is look at the steam review scores for PlayStation games vs. Xbox games and see which company is creating a more positive gaming experience and perception among the paying customers on Steam.
