It is quite simple, there is nothing incomprehensible.
The word "documentary" generally refers to a investigation
video story about a piece of real-world history or circumstances.
The word "document" generally refers to files, maybe pieces of paper, and by extension has come to refer to computer files.
I believe this was the only confusion. If anybody substitutes the word "document" in where you said "documentary", then I think that everything you said makes complete sense.
However, there is one area where you can help us to help you. We do not know which
version of the Warcraft III game that you are referring to as "Classic". It seems that you referring to "Warcraft III Frozen Throne Patch 1.31" as the "Classic". It is important to note that this version was developed by the Reforged team.
In fact,
the only versions of Warcraft III that will use Documents/Warcraft III/Maps
to store and view Map Files in the game are versions created by the Reforged team. So, if you want to use a version of Warcraft III that
does not use the Documents folder in any way then I would suggest that you use a version of Warcraft III
from before the Reforged team started their work at Blizzard. As far as I know, the newest patch that meets this criteria would be Patch 1.26 from 2009 or so.
Also, it is worth noting that
Patch 1.26 has a severe security vulnerability so that maps that you play on this version could have a virus. However, that version will only
look for maps inside of the game directory and so I have 15-30 copies of the Warcraft III game that I backed up over the past 15 years and with these older versions they are all "self contained". They only use maps that are in the folder of that copy of the game. It is a different way of thinking.