> try to make yourself the person in a group surrounded by japanese.

I don't need to try to do this, close friendships with Japanese people and integration in social circles where I'm the only non-Japanese has not been hard. The strategy is just not to have your own preconception of outsiderness.

I see many that complain about difficulty integrating similar to your comments, blaming it on something about the Japanese people. But they themselves didn't make the effort to learn the language or make friends in a more casual way, so it just seems like a responsibility deflection. Maybe this is what you mean by it being really tough, but it seems a pretty normal amount of effort when immigrating to me. Pushing this narrative that it's really hard (some of the language even made it sound like implying impossible) doesn't help make it easier since then people get this preconception of being an outsider, and yes that will do a good job of preventing integration.