EDIT: You know, after some time to cool off, Google Authenticator 2FA can still be enabled and isn’t being phased out like the less secure SMS 2FA, so it’s really not the end of the world here. The chance of permanent lockout is avoided, even if the whole Google Prompt system is still wack.
Mxroute, zoho, m365, migadu, fastmail. Even icloud plus can do mail with a custom domain.