Wanna know the real truth? It's the sex tourism. As an American man, you feel a great sense of superiority in Japan; it is a land you conquered, it's doing worse than your country and its fate is in your hands. My cousin works in fashion and visits Japan every year; she says the men have no vigor and the women are sick and desperate; if you can talk to her, you win. No competition. My Korean MD PhD gym buddy went to Japan for a conference like 10 years ago; he said he's the strongest-looking dude there even though he looks just above average in the US and he can't get the girls off of him! Drunk girls wanted to take him home from the conference and he was calling them cabs to get to leave cus he's already engaged. The economic downturn makes Japanese women even more insecure and easy to target. So while China's still cheaper for your buck (as long as you stay away from the traps), the feeling is totally different because China is a society that the combined West cannot defeat and immediately, the magnanimity and technological superiority in the major cities will humble tourists. People call out Shanghainese for white-worshipping but Japan is on a whole new level; an American pickup artist once went to Japan to demonstrate that he can grab random women on the streets by the hair and force their faces to his crotch in BJ position and they will not scream, fight or call the police; there are no consequences and nobody came to stop him. He was only retrospectively banned from re-entering Japan after his videos went viral when he was back home in the US. This happens anywhere in China, he's getting curbstomped by the locals, jailed, then deported.
When I was a young teen some 2+ decades ago, I had a phase where I was into anime, I wanted to visit Japan and I wanted to marry a Japanese girl. My dad told me that I am Chinese; I can get the best from my own country but the best in Japan are reserved for the Japanese. I would only get scraps as an outsider. Throughout all the years he raised me and taught me, I can count the number of times my dad has been wrong on 1 hand, and he has never been more wrong than this. But I'm happy I listened cus if I knew it was gonna be this easy, I would have cut out of high school, packed my bags to the land of the self-F, and set out to catch 'em all!