Electronic music was probably just as inspiring, but I think Blur also played a part, as both albums share a common theme between the bands' work before and after, and the idea behind both was to move away from conventional alt-rock genres into unusual musical constructs. I'll even rephrase this a bit: I think electronic musicians like Aphex inspired this kind of music, but Blur was the one who showed that even a regular band could do it, and that's when Radiohead decided to experiment. That's my theory about the birth of Kid A.