I’m glad someone else thought about this!!

William Gibson himself talks about this in the retrospective introduction to Neuromancer.

It took at least a decade for me to realize that many of my readers, even in 1984, could never have experienced Neuromancer’s opening line as I’d intended them to. I’d actually composed that first image with the black-and-white video-static of my childhood in mind, sodium-silvery and almost painful—a whopping anachronism, right at the very start of my career in the imaginary future.

The color static of the image above is predictably incorrect.