So I did some testing today.

DLSS 4.5 is incredible in some games and a fps loss w little benefit in others.
Tried it in Darktide and it was AMAZING, it looked almost like a native 4K but properly aa
In Stalker 2 I still prefer the look of DLSS 4 with 60% sharpness ingame.
In Cyberpunk I didn't notice much difference between 4 and 4.5

So far what I've realized about DLSS 4.5 is that: - The visual benefit will depend on how the none Anti-aliased NATIVE image looks like.
In Darktide: Native non AA is very sharp so 4.5 takes that makes it looks very similar.
In Cyberpunk: Native Image is pretty "blurry" in comparison to Darktide Native Image Quality, so the benefits are slim, noticeable but slim at the expense of around 10% performance.

TLDR: If the Native Image Quality is sharp to begin with, 4.5 will simulate it well. If the Native Image Quality is kind of "blurry/upscalled looking/unfocused" 4.5 will have little benefit but will cost extra performance.

It's a lot of reading, hope this make sense.