If you come to Japan as a tourist and say “I love Japan so much”, I think no Japanese person will treat you badly. However, for long term residents, it is totally different.
When I first came to Japan, I was like a straight kid. When I was asked “Will you go back to your country”, I would honestly answer “Nope, I love Japan so much so I want to live here forever.” Then people’s facial expressions would become as if I had said something crazy.
On two occasions, someone told me what they really thought after my answer above. One guy replied “Go home” and another guy said “How?(No way.)”. Basically most people would treat me like a potential illegal immigrant although I don’t know why. I guess maybe they thought I was too dumb to live here legally.
Eventually, I changed my strategy. Now I pretend that I don’t actually like Japan. I say “I’m not sure. Maybe I will move the US soon” or “Europe is not bad, actually a Danish university might give me an offer.” etc
Sadly, it works, and works well. People now seem to be more satisfied reacting to this kind of conversations. They treat me better and everything seems alright. I just have to hid my love in front of Japanese people sometimes.