First, Japan had a mindblowing consumer electronics industry way before we did. There were special purpose devices for everything you could want. They were all user friendly and did not require understanding how the underlying system worked. They didn't need a PC since all their electronic needs were already met and met better.
Second, Japan is basically 99% urban living, as space is at an insane premium, and even when you are in the country the houses are built small due to culture and lack of open space, since if you're not in the city you're probably in the mountains. This means there was no physical place to even put a PC in most Japanese houses the way American houses might have a desk in a corner or even an office.
Third, and probably the most important, phone calls in Japan were always pay by minute, even for local calls. This meant that if you were online with a modem, you were paying the phone bill just sitting there. This meant that if a person even had a modem, the would rarely use the internet. Since America had monthly-billed phones, there was no problem staying up all night on AOL chatrooms, and AOL really was the killer app that pushed PCs into American houses.
IMO this is why the PC revolution that really took off in American homes, and by association a bunch of us who cut our teeth mucking about with bat files so we could play our DOS games and ended up learning useful skills out of necessity never happened in Japan.