Thanks EconomiCurtis. I may be onto a solution.
Google Drive recently became Google Drive File Stream. I researched similar problems with Mac and MS Office products. Most of those didn't work, then I found an article on unacceptable path names for remote drives.
Well, GDFS is like a cloud drive with the possibility of locally saved "offline" files. So, I dug around and found this, https://support.google.com/a/answer/7644837?hl=en
I ran a system-wide rename of the mount as
sudo defaults write /Library/Preferences/com.google.drivefs.settings DefaultMountPoint '~/GDriveFS'
This seems to fix a problem with saving that I just noticed in Office (I had not been using it on my Mac until a week ago.) It seems to have fixed saving problems in Office, so I will update you in a week or so if I see no more pink dots.
I know that is a lot of detail, but this is likely hard to reprex. Maybe try Google Drive File Stream?