Unable to add a Google account to my iphone

I've been troubleshooting not being able to add a Google account to my iphone 6s with iOS 12.2 installed. Right now, if I attempt to add the account through Passwords & Accounts -> Add Account -> Google, it asks for email address, password, I verify my identity on my other phone, and then the iphone switches to the email account page for my new Google account (with the green switches for mail, contacts, etc) and then, after a split second, that disappears and dumps me back to the "Add Account" screen (where you can select from iCloud, Exchange, Google, Yahoo, etc). Going back one screen to the Accounts page shows no Google account.

I've tried turning off 2-factor authentication on my Google account - no effect

I've tried restarting the phone many times - no effect

I've tried manually setting up the account - the account saves, but is empty (no emails, can't send/receive)

I've tried a factory reset, and then the first thing I did after finishing the new device setup was attempt to add the Google account - same results

I've tried using all 3 of my Google accounts - all 3 of them gave the same result.

I've consulted with a colleague, who also was unable to add his Google account to his iphone.

At this point I am inclined to think Apple has blocked adding Google accounts to their devices, but if this is true, why would they not remove the colorful Google icon from the list of email accounts you can add?

I was able to install Microsoft Outlook and add the account through there. The Gmail app also works very well. But neither option will add my Google contacts to the iphone...