Today I was helping a user with an Outlook issue and I tried checking to see what protocol Outlook was using to connect with G-suite Gmail (i.e. Gmail for organizations).
This user's account has POP and IMAP turned off and it's on a Mac, so it's not using the Gsuite sync tool.
The user set it up by just telling Outlook to connect to a Google account. I had thought this used IMAP and I believe it did in the past.
Any ideas?