For two people to play splitscreen the console has to essentially to run the game twice to account for both players. Even though both players are in the same area interacting with the same enemies, the graphics card has to run both screens fluidly while the CPU is accounting for both players actions and how they influence the game.
You also have to account for players separating and exploring different areas that the game then has to load simultaneously and display on the same screen. What if player one is inside shooting a bunch of enemies while player 2 is outside in a banshee way up in the sky? The Series consoles can probably manage it, but it wouldn’t surprise me at all if the base current gen consoles make it a near impossible task. I think OG xbox 1 can only play this game at 30 fps as it is
Meanwhile Series X can seamlessly swap between 60 FPS & 120FPS at any time in the menus.
Along with the rise of online gaming, I think this is the reason why splitscreen gaming has somewhat died in the past several years. Most games are doing too much to have a legit split screen experience. The few games that are splitscreen nowadays typically aren’t very graphically taxing, like Borderlands. Gears 5 has splitscreen co-op but those are more linear levels with much less mobility throughout combat. You’re not using the grappling hook to quickly repel 3 stories up and jumping around climbing anything you see in a large open area
