the only reason a video game needs its own, ingame screenshot function (seperate from steam's or that of your OS/a third pary app) is if it saved the game state, not an actual picture, and let you change graphics settings afterwards, letting you render the image prettier (or for example in UHD when you're playing at 1080p or 1440p).
However, no game i know has ever implemented screenshots like that
#gamedev #gamedesign