We were talking about integration. If you are happy more or less ghettoing yourself that is right.
But we were talking about being accepted. It os really difficult to be accepted in japanese circles as one more. But it is not the case, for example, in Spain in comparison.
I was not talking about having the apprpval of others. I do not really care. But in order to get integrated there are cultures that are really flexible, others are more stiff and others it is almost impossible.
Japanese people have trouble being accepted in circles of Japanese people.
All it takes is speaking the language fluently. Hard but this mystery behind integration isn't complex. So much of the culture is expressed through language. Sound native and you will be treated as native (for better and worse)