[cyorir]

So let us make a few distinctions. NEET =/= Hikikomori. Hikikomori tend to be a subset of NEET, as long as they are not employed. However, most NEET (not in education, employment, or training) would certainly not be Hikikomori. Hikikomori are the edge case, so only those who have no hopes of moving towards employment AND no desire for external interactions with society will likely be Hikikomori.

The preoccupation with Hikikomori began in the 90s, when someone made the now infamous claim that there were roughly a million Hikikomori in Japan, setting off an alarm. That seems to have been a gross overestimate, but it put the term in the popular lexicon. More recent studies offer more conservative and more realistic estimates.

It just so happens that the popular view of Hikikomori is that they tend to be very focused on specific subcultures, so in particular they are commonly characterized as Otaku (although there would be Hikikomori who are not Otaku and most Otaku are not Hikikomoris, etc.). These characterizations (hikikomori as someone obsessed with a particular pasttime/lifestyl, and hikikomori as extreme NEET) have generally formed the basis for the Hikimori as it is sometimes portrayed in anime.