Unpatched games will get certain benefits as well.
The Xbox One X will have system wide supersampling, which we know will have benefits for even users on 1080p screens, because it will enhance visual quality. Now, we have some more details on what kinds of visual benefits the supersampling will bring to the table for ‘enhanced’ games.
Xbox One X enhanced games will get texture improvements, faster framerates, and improved image quality, even if you are on a 1080p screen, as reported by The Verge. Unpatched games will get benefits from the Xbox One X and its featureset as well- these may include faster loading times (the most obvious one), as well as better framerates, and enhanced visual quality all around. More specific improvements will be contingent on the developer patching the game for Xbox One X support.
It all certainly sounds like the Xbox One X will end up delivering more visual improvements than a PS4 Pro does. The Xbox One X is due out on November 7, with pre-orders for the console now live.