I confirm that the ketotek suggestion is correct.
Don’t know why, as squasfs files are for definition read-only, but adding “-o ro” make the mount of squashfs files possibile.
The mount time of a remote squashfs is not exactly fast with HubiC: it took me 2m46s to mount a 55GB squashfs file.
It took 3m23s to explore the directory structure of the squashfs file which contained 118.000 files.
I will try to test later with Google Drive.