You are also missing that American soft culture is even stronger than what Japan exports. It's just been around longer and normalized for so long it is just normal to consume American media outside the US. I've ran into people that know more about US laws than the laws of their home country just from watching US television

As for Japan, it's not just the western nations. Taiwan also has a huge fascination with Japan. Many Asian nations have like Japan for their strong soft culture, but detest the Japanese government for historical treatment of these nations. Japanese and American governments are heavily invested in soft power. Here is a long but interesting video discussing Japanese soft power https://youtu.be/IM2VIKfaY0Y?si=H0gRcyKtu4kMUaCj

South Korea has also had a lot of success with soft power. It's just had a later start than Japan and the US.