I've been playing on Mac and switched over to Xbox and was surprised to see significantly reduced visual quality, there. I've attached three side-by-side screenshot comparisons, described below.
• Mac (Fullscreen 1512x945) vs. Mac (Fullscreen 3024x1964)
Even with the difference of upscaling to monitor output resolution, there is again almost no distinguishable visual difference between the two. Both look equally clear. This is my "baseline," essentially.
• Xbox Series X (4K, 70% CRT, 50% Shake) vs. Mac (Borderless ~4K, 70% CRT, 50% Shake)
I would expect to see comparable resolution/clarity, but Xbox is significantly muddier, enough that it's pretty hard for me to play without dropping CRT and Shake to 0%—and even then, looks a lot worse than Mac.
• Xbox Series X (4K, 0% CRT, 0% Shake) vs. Xbox Series S (1080p 0% CRT, 0% Shake)
Here there is almost no distinguishable visual difference between the two, despite the significant difference in tangible resolution. I've used the no-shake, no-CRT versions here, but it's pretty much the same with them turned on.