At least for marketing (the only industry I have experience with), I simply don't think that anyone is entitled to an opinion if they haven't worked at a Japanese company.

As you said, Japanese companies are a reflection of Japanese societies. If you don't understand how that works, you simply cannot nail the localization in a way that works.

For example, if you don't understand ringisho and the decision making process, you might come up with some campaign that would work in a society were someone has sole authority to decide.

Also, many of the people who are negative haven't put in the time in the trenches to build enough credit to reap the benefits of a Japanese company.

I did 10 years at a listed company before I went freelance but even now they are my biggest client and regularly root for me despite no longer being an employee.

If you put in the time to become "one of the family," Japanese companies will take care of you in a way that gaishikei just won't. No one wants to go through the phase of earning your right to the family though...