I'm not sure what you think I didn't get - or what new questions appeared over your head. It's quite simple. You said 3 things:
1) You answered to the parent that whether "term may not map cleanly to a single OOP class" doesn't matter, because "it will map to either entities or functions".
My answer was that it might not map to those either, but still be useful to talk about the software, and good to be shared by the developers and other shareholders like UX and sales.
2) That "An argument against documenting it on the entities and functions would be that this would spread the information across the repository", and having a single markdown file gives better overview.
I agreed, and even expounded on that: "it would be a bad idea to have the developers (and especially non developrs) hunt them around (even if it's just a grep away). As you say, the overview is important."
3) That "these kinds of methodologies enable development with high turnover in large enterprise, which treat developers more like cogs that temporarily work on a given software. And if it's just a comment on a file, it'll likely not even be seen"
And I retorted that even smaller teams - meaning teams that don't are anything like the above, including not having high turnover, can benefit from this. Even without any turnover, people forget. So when getting back to further develop or debug or refactor, etc, some piece software it's good to have documentation of key types, concepts, and terminology, from when you originally wrote it.