I installed MSFS (from MS Store, not Steam) in a separate SSD. For example, the Community folder looks like (I modified the numbers / letters) as follows:
You will get this path if you tell the MS Store where to install Apps OR you have used the “Move” app command after an app has been installed.
For a shorter path, use the install to location in the MSFS setup.
Doing this you can tell it, for example: E:\MSFS
Some files will still go to drive C: as that is how apps work but the all main large files will be in E:\MSFS
If you uninstall MSFS, that E:\WpSystem folder will still be there. The only way to rid of it is to format that drive. Take caution about doing this if you also told other MS Store apps to go to the E: drive or you setup the MS Store app to always install to that drive.