I don't think it is, not for a business such as the one described in the article. I'm currently living in Japan, and in a relatively short amount of time I've personally met several business owners who might have acted similarly, sincerely.

There is a large amount of small and niche businesses here which are not profit-driven.

I am inclined to agree with you, e.g. the number of very long-running family businesses in Japan, traditional arts being kept alive, etc.

otoh unless you've lived in Japan for a very long time it's pretty hard to tell what is sincere and what isn't in a public forum.

Weekly afterworks and 12 hours work a day will force you to feel like a family wether you like it or not.

Also if your mindset festers they will stop being polite which is way worse.

I took that to mean that if you fail to continue to be productive then your colleagues will cease to be polite to you, is that correct?

It's up for debate how productive Japan's companies really are.

Studies show it is one of the least productive/efficient among developed economies, with all the unnecessary meetings, lack of quick decision-making, and outdated processes.