That's not what hikikomori are. Hikikomori shut themselves in and interact with the outside (real) world as little as possible. You don't even have to be a NEET to be a hikikomori, and there's no implication of social withdrawal with NEETs.

I think it’s because a NEET in other places, like Italy or the US, is not a shut in 99% of the times

I'm not sure that's true. There's a lot of young people (particularly boys) who sit home at their parents and do nothing but play video games and never go out:

https://www.washingtonpost.com/business/2019/03/29/share-ame...

I'm not going to go deeper in the topic as it has been discussed to death in many places, but I do believe that there's a metric ton of young people who are disengaged from society.

For sure they are correlated but it's not 1:1

There's a huge difference between NEET (which basically everyone goes through periods of) and complete shut-in.

definitely culture expectations. Japan is a very conformist society that expects every member to contribute. So someone more or less dropping out is a big deal, for them and their family

China is similarly an Asian country, with demanding social roles and other struggles as well. They have significantly more people and landmass, and so, opportunity for the diversity of phenomenons like this, and yet, they are much less visible than Japan's. The difference, I think, is in PR. Whatever Japan has, they turn it into pop culture, and they use that pop culture to strengthen the idea that Japan is somehow interesting. The feeling I have about China is that they rather want to project one specific image.

So I feel it's less about how the society is structured, and more about how each country positions itself.

> and yet, they are much less visible than Japan's.

I feel that's by design. China's been more hostile to the West than Japan over the past decades than Japan/South korea. In some ways, the red scare never truly ended.

It is indeed PR, as you said. I'm sure it's even worse in China, but China wants to look like having a pristine image (due to the above situation). Japan is definitely closer to the western mentality where they would turn such a story into an episode of Hoarders or something of that vein if they could. There are indeed a dozen decently known anime based around the Hikkimori lifestyle.

The way I see it, Japan is an Asian country, and fascination with Asian countries has a long history[0]. The other thing is that Japan has a vivid pop culture since WW2 and really ramped up its soft power effort, of which a significant aspect is the export of the Japanese culture in general [1].

The phenomenon OP is talking about is excellently captured in the "Thing, Japan" meme as well [2].

[0] https://en.wikipedia.org/wiki/Orientalism

[1] https://en.wikipedia.org/wiki/Cool_Japan

[2] https://knowyourmeme.com/memes/thing-japan