No, it's not wrong to assume that all Japanese women are into karaoke, but it is important to remember that everyone has different interests and preferences! While karaoke may be a popular pastime among Japanese people, there are plenty of other activities that some Japanese women may prefer. When considering dating a Japanese woman, it’s important to be open-minded and get to know her better before making assumptions about what she likes or dislikes. Ask her questions about her hobbies and interests so you can better understand who she is as an individual. It’s also helpful to research more about the culture in Japan so you can learn more about their values and customs.