Hmm, I do remember both. It was not even grey, static is high-contrast flickering of b/w dots or short lines with an amount of random grey between them (maybe soviet static was staticker, idk). For me and sky, blue makes sense, static just doesn’t. If I read it before blue screens appeared, maybe it could.
Static also has the quality of lacking scale, and containing spurious signal that your visual cortex tries to lock onto but never can. I always read the neuromancer sky as having that same kind of depthless gray and false motion that I associate with tv snow. A color you can see but can’t rest your eyes on.
I think you are supposed to view the CRT from a bit afar, then you'd get that gray feeling. Also these "bands" were either jumping too much up and down to be noticable or not appearing at all on the old purely analog sets. As I remember them, the static was truly chaotic, no lines.
I guess it may depend on a signal saturation. Some empty channels were relatively dim and sparse, and some screamed white morse at you. That picture is not exactly what we should have seen, for one I cannot count 500+ lines in there. It must be only a part of a screen or a non-standard resolution (or a very short expo that captured half-frame?). Couldn’t find a good one quickly.
https://www.canstockphoto.com/real-tv-static-10531607.html