Can you suggest a better comparison?
Direct comparisons are difficult as few scenes will show areas where Odyssey is actually destroying information or resulting in a scene that cannot be salvaged with appropriate settings. Best ones I can think of are ships and other assets that have the same geometry between 3.8 and 4.0, in lighting conditions that are supposed to be similar, with neutral colored paints, where possible. Cockpits themselves, especially Imperial ships with white interiors, aren't bad.
The skybox is one of the most customizable parts of the view and I just tune it to look more or less what I think I would see from the vacuum of space, with minimal embellishment, on either client. It is darker in Odyssey, and there is a deliberate muting of the more fanciful elements, but it's also not outright missing information like other parts of the scene can be.
Minor JPEG compression artifacts aside, this is the Milky Way I see from within the bubble (specifically LTT 5455, 32k LS from anything), with my usual settings:

But I can also make it look a considerably brighter by changing a handful of variables:

Swap out another two for a five and stick a random seven in there it gets really absurd (I logged in and thought Praxis had exploded):

Some people did prefer Old Horizons though, and it certainly did look spectacular...but I really doubt the milkway looks like that to any human eyes from anywhere:

Keep in mind I have my display calibrated so that I can see everything that's in the first image. If turning up brightness reveals more, chances are one's display has a fair degree of black crush. Black crush is also what Odyssey itself does to some dark scenes, but not so much the skybox.