I beg to differ. There's no official answer for this question.
However, ProgramData and AppData folders are hidden and Saved Games is much more accessible - it is used for user mods as well as user settings.
You seem to be using Saved Games as an install folder for games - this is the first time I see such decision, which also proves that there's no single answer how to user these folders.
IMHO, it is not a good place to install apps because it is writable by anyone. Program Files is a much better location. protected against unintended (or malicious, by other apps) changes.
If you are interested in a dispute on the topic:
https://steamcommunity.com/app/427520/discussions/10/1480982338959015492/