In this case, Japanese IP laws, which are among the strictest in the developed world. That’s what allows Nintendo to legally throw their weight around like they do. And given that Japan is the home of many of the world’s most valuable IPs, not just in gaming but in many other fields, not to mention the fact that corporate control of the gov’t and society is on a whole other level there compared to the West, don’t expect those laws to change any time soon.