> US tech mega corporations are dominant rather than Japan
At the risk of going way out into tangents: Gibson's books had a fascinating mix of tech mega corporations, not just Japanese, but some of the big players were European in origin, and a share of US tech mega corporations.
Gibson absolutely has a kawaii bug about Japanese culture, though that's not his only over-fascination (arguably more of the Neuromancer trilogy is bound to voodoun fascination than Japanese culture fascination), but the important point at the time, and still a useful timeless quality to Gibson's books was how much Gibson got right about the increased weird of a global mega-culture. Much more so than most of his contemporaries, Gibson's cyberpunk much more accurately captured the feeling of the internet before the internet: one minute you might be watching K-Pop on TikTok and then some dude with a Voodoo-based handle sends you some weird files on Discord, before you hop over to Facebook for the latest Eurovision memes.
Gibson used the prominence of Japanese mega corporations not just because a lot 80s tech stock pundits (possibly wrongly; though Sony et al still have a large market presence) thought the Japanese would dominate the future, but as a part of a larger cross-cultural package that the future of "punk" wasn't just white-bread American but a stew waiting to be stirred of global culture. In that Gibson is an interesting comparison to pick when comparing timeless versus time-bound components of cyberpunk, as Gibson's Japanese focus I think was by far one of his most timeless additions to the genre.