Its probably good enough to run any 4K games the same at 1080p with a decent amount of optimisation work, that's 4x less pixels. 1440p is going to be a struggle, maybe if a game is 4k60 it can run 1440p30. Also RT is only gonna work at like 1080p30yeah, but you are assuming that games on xbsx going to be 4k60. that would be, imo, "holding games back". you can already see that 30 fps is still going to be the standard on ps5 with sub-4k native resolutions to give more processing power for "other stuff". oh sure, developers could target 4k60 but as we've seen over and over and over again that means holding back games in other ways.
xbsx will certainly be capable of 4k60 on games like "ori" but for true next gen AAA games it won't be. ...or shouldn't be. it will be sub 60 fps and/or sub 4k native resolution. scale back a game designed for ps5/xbsx at 1440p30 to xbss and what are you left with? either really low resolutions and framerates or (more likely) developer work to reduce the number of objects on the screen to get back up to acceptable performance.
