Hi. Yes and No
1. Some S24 ultras have issues with grainy screen and / or banding.
This has been well documented if you check here or just Google for it.
I haven't seen the grain issue on mine but do have the banding issue.
The banding is mostly visible on grey areas for me mostly on YouTube videos where the youtuber has a grey background.
It's annoying Yes.
But it's just the way the new antiglare screen on the s24 ultra is designed.
If you just got the phone and it bothers you maybe see if you can get it changed.
Otherwise it's just an annoyance now and then and may not really count as a defect. ( which it is).
Hope this helps.
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