With MSFS, everything is evolving.
I have always had FS2020 install on my D: drive.
I moved it there with the Windows Apps, MS Flight Simulator App
“Move” command.
It did move FS2020 to my D: drive but left the “Installed Packages” on C:. Basically, copied the Packages from C: to D:.
I did, back then, go to C: and deleted them.
Now, I only have FS2020 installed initially from MS Store/XBox
directly to the D: drive. Thus the 5.32 MB.
My C; drive only has the Symbolic Links to the FS22020 folders on the D: drive. They do not occupy drive space.
Look at this Topic. Also applies to Windows 10.