The problem is they need a Steve Jobs selling them on iPhones more than anyone else on the planet, and they almost never get their own "Steve Jobs" especially these days.
For a software example, consider LINE: The most popular instant messaging platform in Japan. It's owned and operated by a Japanese company today (LY Corporation, or the LINE Yahoo Corporation), but LINE is originally a South Korean piece of software engineering by Naver. Japan couldn't make their own product because "Why?", email and texting are fine they say; South Korea had to show them why.
A particularly egregious example is Toshiba putting the inventor of NAND flash (Fujio Masuoka) out to dry and claiming the technology was invented by Intel, because they so utterly hated the idea of creating an entire new market and needing to answer "Why?" when hard drives and floppies and tapes were just fine.
Japanese people are too capable for their own good, arguably they are so capable they are incapable.
Incidentally, Japan is still trying to make the metaverse and NFTs a thing. That should tell you all you need to know about how stagnant the Japanese can be once they're satisfied.