It's another "theory about Japanese" (日本人論), people making stuff up that makes the Japanese sound unique, like that Japanese are descended from different apes than other races, or that Japan is the only country with four seasons.
Every country or people have their own ideas about how they are awesome, but I think I noticed it here because I'm an outsider.
I think in the end 日本人論 is just another form of supremacy, in this case Japanese. Notice the contrast to American exceptionalism, where a reason for USA Number 1 is often not needed, whereas nihonjinron usually requires some reasoning as to why the Japanese language is superior, or why Japanese brains are better, or why Japanese culture is exceptional. It is a very self-conscious way of exceptionalism :)
To be honest, I'm quite sick of any cultural glorification from any country. But given how Japan never went through a cleansing after their fascism (unlike east/west-germany after '45 and '68) I can understand that there is not a lot of self-awareness in that regard.
In some sense the youth is trying to distance itself from the problematic past by becoming apathetic consumerists.
Every time one of these articles crop up, I feel that someone is viewing Japanese through some heavily rose tinted glasses.
Every country or people have their own ideas about how they are awesome, but I think I noticed it here because I'm an outsider.