So I'm not the typical S24 ultra owner. I've updated every cycle since like the S7. I went to the ultra when they started putting a lower definition display on the normal sized phone. I also personally own S24 ultras, and have access to a 3rd.

I had a feelin early on that my displays were different. A few minutes ago I spent some time checking my settings. Both phones had 1440p and adaptive refresh rate as well as vivid mode turned on. Then I messed with color temp as well. I also checked extra dim on and off and compared across those 2 devices.

What I'm seeing is that my 512 gb green device seems to have blacker blacks and whiter whites. As a result the display always feels brighter. I had this feeling since day one. My other s24u is also 512 but black. I received both on the same day. Both were ordered from Samsung 2 days apart. I notice the display mura on the images that are posted but not on any of my devices. I think the easiest way for me to describe it is inconsistent brightness or contrast.

I will try to remember to check again in a couple of days. Plot twist I also have access to a blue 512gb s24u that was also received on the same and order from samsung. Yes the were all pre-ordered and all 3 are unlocked. So I'm gonna check that in the same low light conditions. I'm also gonna try to check all 3 displays with higher screen brightness (during the day AND if people seem to care).

Tl;dr: display nconsistent brightness or contrast. Own 2 s24u, and have access to a 3rd for testing.