My personal experience moving from CA to Japan is that despite the national taxes being higher than the USA, it pencils out to less than what I was paying in the US because of CA’s high tax rate, and I get a functioning healthcare system to boot.
Are you a developer in Japan? What is that like and what space do you work in? I’ll never be able to move to Japan but it sounds very interesting to me.
I'm working remotely for my startup I built in the USA, so I don't know personally what it's like at companies here per se, but as the other commenter said, wages are considerably lower on average - though I've heard that it's generally higher than the wages in Europe. Seems that $40-70k is a fairly normal first job wage for a bootcamper for instance.
The culture at companies is extremely dependent on the company - a traditional employer might expect the prototypically Japanese extreme deference/obedience to hierarchy, but it also seems that there are plenty of companies that "get it" and don't play that game, as well as the full set of FAANGs and foreigner-run companies that follow a totally different set of rules than the old school businesses here; and it's also subject to change considerably now that model companies like Toyota are moving to merit- instead of loyalty-based promotions, but that kind of shift takes a long time to take hold.
Your job options are much smaller if you don't speak Japanese, but jobs exist, I know people who have gotten them, and they tend to be in the international- or international-style companies. Wages for foreigners strangely are generally decently higher than for locals, I hear, even if not knowing Japanese is more of a handicap than a help lol.
Coworkers at Japanese company with site here in California relayed to me the pay was 3-5x less circa 1990s at least, many developers there can speak English but being fluent in Japanese would help a lot (even necessary at times) in work situations and outside work.