So... where is the money coming from? Who is going to pay for this multitude of professional programmers to converge to the same environment, be vetted, and spend a non-trivial amount of time coding the same thing as the others in the group?

Of course the researchers in the article would have loved to have those kind of resources and do the perfect, wide-ranging, deeply detailed study, but the OP's criticisms just show how divorced the OP is from experimenting with real-world humans in real-world situations, and with real-world resources.

The research presented here is weak. Honestly pointing that out without pulling punches is better than simply giving them a pass because 'doing good research is hard'.

It'd still not be easy, and of course there'd still be issues (e.g. is there anything about the corporate culture or training in that company that would affect the result?), but it'd still be far better than a bunch of students and toy problems.

Though I think we could derive some more realistic scenarios, like evolving requirements and switching developers mid project that would be more enlightening.

As others have said, good research costs money...

Hackatons seem to manage. Why not set one up?