The author is one of the "core team" members of Django[0]. So, it is safe to say that whatever assumptions he has about open source is not a fantasy and cannot be compared line-by-line to a text book definition of open source.
Why not? The OP claims that his opinions are explicitly mentioned in accepted definitions:
> some of which are explicit in accepted definitions of the term
If the OP is going to make that claim, why should we not expect to be able to find validation for his assumptions in a written definition of open source?
I no way am I going to accept anyone's opinion based on what project they are associated with. If Linus Torvalds says something about open source or free software, I'll read what he says and make my opinion based on what he is saying, not based on that he was the original creator of Linux.
Anything else is just appeal to authority and we would do much better in discussions if we didn't do that.