Darius Kaunas regular yubikeys don't work on iPhone — Yubico just released a key that you can plug into an iPhone, but I haven't had the chance to test it yet and I'm not sure it works with Google SmartLock.

I think you have 2 options here: 1) you buy a security key with BLE support such as the Google Titan, Feitian, or SecureClick; 2) you temporarily disable Advanced Protection, set up your phone with just a regular 2FA code, then re-enable AP.

Hopefully things will improve soon, and we all stay more protected! Thank you for reading this post.