Oddly enough, the dashboard of Microsoft's Xbox Series X is not 4K, this is despite being a console released with a focus on actual gaming in 4K resolution.
The dashboards of the Xbox Series X and S and all their accompanying UI elements have been rendering at 1080p resolution since the consoles' launch.
Now, finally, after continuous complaints from the Xbox gaming community, Microsoft has announced that a new 4K resolution dashboard interface for the Xbox Series X is in testing.
Microsoft's Xbox testing team states what 4K brings to the table:
This change means Home, Guide, and other areas of the UI will be displayed in a higher native resolution for increased sharpness and text readability.
It is important to note that the improved resolution will apparently not demand more resources from the console.
Readability was one of the most common issues that players encountered on the 1080p dashboard. The arrival of the 4K dashboard should significantly improve the readability and sharpness of text on 4K monitors and this is where most 4K users have reported that fonts are teeny-tiny.