Hikikomori, Japan's social recluses
nationalgeographic.com
nationalgeographic.com
Though I can appreciate their perspective. If society around you is a frantic rat race, and you're not allowed to live for yourself, and it doesn't seem to make a difference what you do, then why bother?
I don't quite feel the same, but I admit much of modern life is so discouraging as to be a farce of a civilization.
Social isolation seems to be a big part of it. Friendships, jobs, and even family ties feel fleeting and superficial. Why work on building a life when everything shifts so much that your environment, activities, and social contacts completely change every couple of years?
I guess if you name a thing it becomes a thing.
I think the definition is accurate enough: people who recluse inside their rooms or houses for extended periods of time and don't have any real life social relationships.
So not just 'lonely'.
Also to get food at night in Japan doesn't necessarily mean that you have to interact with people: I've heard you can buy pretty much anything from the vending machines.