It really depends on where you have the sim installed, and also whether you are using the Steam or MS Store version.
So for me, the sim is broken up thusly.
C:\Program Files\WindowsApps\Microsoft.FlightSimulator_1.33.8.0_x64__8wekyb3d8bbwe
This is where the sim executable is installed. When you use the XBox application to prompt an update of the sim, and you get that ~2GB download, this is where it gets stored. This is not where the bulk of the sim is installed, which is where you would find planes, and airports etc.
C:\Users\%USERNAME%\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe
This is the folder which has the “LocalCache” folder, amongst other things. There is also a folder that contains you logbook, and controller configurations. This is where you found the “state.cfg” files, one per plane.
All of the folders except one are “Junction Points”, which means the folders are actually elsewhere on the system. For me, presumably because I chose to install the sim on my “D” drive, they actually exist in:
D:\WpSystem\S-1-5-21-3738441901-1295518950-3516428421-1001\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe
The long number is the SID of the local user account that has MSFS installed.

This is also where you will the following file, which points to where you have the sim proper installed.
C:\Users\%USERNAME%\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\UserCfg.opt
At the end of this file, which has graphical options for the sim, it has the location of the bulk of the sim, which for me is:
InstalledPackagesPath “D:\Flight Simulator”
This is where you will find the “Community”, and “Official” folders. Non-Marketplace purchases are stored in “Community”. Marketplace purchases will in “Official/OneStore”.