I've run into this today. After much troubleshooting, I was able to reproduce the issue on my laptop by installing Google Drive File Stream (GDFS). After uninstalling the problem goes away.
With GDFS installed, you can work around the bug by unchecking in PowerPoint - File>Settings>Trust Center>trust center settings>protected view>"enable protected view for files originating from the Internet"
I've reported the issue to google drive. I'd advise other do as well.
EDIT- is anyone seeing this issue who does not have File Stream installed?
