This is another case for only pushing encrypted files to storage hosts, unless it's against Google Drive's TOS or something. Has anyone tried it? Did Google complain?
Edit: there is also the (sorta abandoned, or finished/complete depending on your pov) plexdrive project, which does a bit of Plex server specific opinionated stuff and mounts gdrive read only, but which may help with reducing API quota usage according to some reports. I’ve never had any issues with the quotas that I’m aware of, but I did have to tune my settings a fair bit to get it dialed in on a somewhat memory constrained vps.
openssl enc -e -aes-128-cbc -in ${1} -out ${1}.cr -iter +123456 -k <password>