This isn't really the case; there are more corporate structure/cultural impediments than legal ones, ones which Apple, if anyone, could be able to overcome (if only by dint of having infinite money and resources).In general Japanese law makes hostile takeovers very difficult. Nintendo would have to want to sell.
https://link.springer.com/article/10.1007/s40804-017-0091-1#Sec20
"The perceived low level of activity in the Japanese takeover market cannot be attributed to its takeover law, the Financial Instrument or the Exchange Law. Indeed, a careful examination of the content of the law reveals that this legislation operates in the offeror's favour. "
https://scholarship.law.berkeley.edu/cgi/viewcontent.cgi?article=1122&context=bblj
"Ultimately, by highlighting how Japan's hostile takeovers regime must be understood on its own terms, this part of the article reveals that Japan's regulatory regime has charted its own course—but in a way that has been slow to develop and left many critical questions unanswered. For example, it is still unclear, under Japanese law, what types of defensive measures are legally permissible, how directors' duties apply in hostile takeover cases, and whether independent directors have any role to play in hostile takeovers. We posit that such critical questions have remained unanswered in Japan because other non-legal factors described in this Article (i.e., stableshareholdings and Japanese corporate culture) have effectively shielded the vast majority of listed companies from hostile takeovers."
https://www8.gsb.columbia.edu/articles/chazen-global-insights/why-ma-different-japan
"Although most legal hurdles to M&A have been lowered and transparency is much improved, the Japanese corporate governance norms still protect companies that balk at selling to international investors or hostile buyers"