http://wccftech.com/final-fantasy-xv-xbox-one-x-native-3k-checkerboard-4k/

Final Fantasy XV on Xbox One X won’t run at native 4K, instead it will render at native 1800p (3K) and will then be upscaled to 4K using checkerboard rendering.

Unlike the Xbox One X and PS4 Pro versions of the game, the PC version will support native 4K resolution. That’s what the game’s director, Hajime Tabata, told DualShockers at PAX West.