I'm not quite sure what you're trying to say here, but it sounds like you're saying "Blade Runner wasn't an enormous influence on 40 years of sci-fi, because it

I'm not quite sure what you're trying to say here, but it sounds like you're saying "Blade Runner wasn't an enormous influence on 40 years of sci-fi, because it also had influences and we should credit those instead." I don't think that's how it works. At worst, Blade Runner took an aesthetic that had been the domain of some relatively obscure (if excellent) comics and brought it crashing into the forefront of global pop culture. Also, "cyberpunk itself started in the 1960s" is...pretty questionable. It was certainly heavily influenced and rooted in New Wave sci-fi of the '60s and '70s, but cyberpunk as a literary movement is very much a thing of the '80s. In any case, New Wave sci-fi and Do Androids Dream of Electric Sheep? were very much textual media. They were a huge influence on the themes and stories of what would become cyberpunk, not so much on the visual aesthetic.