It isn't "so we won't investigate any further", it is "we don't think it is the best use of our resources to investigate this" and in my view it also implies "but if you have a good idea for how to investigate it empirically, please feel free to do so".

I don't think "that group" is self-reinforcing at all. Essentially everyone who comes in with no experience comes in thinking "meetings are crap, communication is crap, we just need to write code". Most of those people (but not all!) slowly but surely change their minds as they gain experience. But every one of those people is an opportunity for the thesis to be disproven. Similarly, nearly every new organization is an opportunity to try something new. Google didn't start out with lots of meetings and engineering committees and design review processes. They started out just wanting to write tons of code. They didn't hire management (or "agile") consultants or bring in outside managers as they grew to come tell them how to behave like a big company is supposed to. The people who started out writing all that code and ridiculing bureaucracy are the same people who eventually accrued processes to manage meteoric growth.

I really don't think people are as narrow-minded and closed off to this as you seem to believe. People are hungry for a better way to manage organization growth, it's just a high bar because people have seen lots of these kinds of efforts, and frankly just get kind of bored of chasing "one weird trick to make everyone way more productive" again and again.