I went to check specific parts and I'm of the impression that it's mixed material, whether from older builds or weaker platforms, or both. Now bear with me, I have no idea about technical matters so I'm just writing from a layman's perspective. Would've made gifs if I was more competent.
Zoom-in on Geralt while surrounded by the Wild Hunt - I'm honestly not seeing severe difference between this image (which was paused during a fast-paced scene, lowering the quality) and what we've seen in the 35min. The only thing that felt particularly jarring was the chainarmor part of his outfit, which looks flat. So I went to the 35min video to see if it was much different, and found a few shots where it, likewise, looked flat:
Zoom-in on Geralt's, err, shoulder, during the 35min
So it's about the angles, I guess.
King of the Wild Hunt - Elder Blood trailer - then there are parts like this which look awesome,
Wild Hunt General - and parts like this which look like a parody.
Wild Hunt chasing Yennefer - considering the compression and how blurred this is due to being a chase scene, I think it's pretty good. Watching it in motion is better and I don't see anything different from the 35 minute footage.
Some parts look good, others terrible. I'm not sure what to make of this. Explaining which platform this is on might help to explain. By that I mean, if it's stated to be console, we'll let out a sigh of relief. If it'll be stated to be PC, then brows will be raised. That being said, I don't understand the rationale behind releasing material that isn't the best you can muster. Unless it
is the best you can muster, in which case I'll just not believe you.