Just thinking about this.
The download program will download the data to your PC.
Your PC will then run a Decompression Program (7-Zip Gzip)
to decompress the data.
This is done within your PC.
For my FS2020 download, I watched it and even for the large files,
the decompression would only take 30 seconds (or less) at most.
I don’t know if My Store is downloading the decompression software and then using it or if it is using the decompresion software that
is on your PC.
Decompression should be a local task.
Maybe it is being done from the cloud.
Anyone know?