Shoving yet another banner in the user's face that is styled like every other banner ad you place in their way, including the one that begs you to download chrome or to sign up for google's latest service does not constitute a meaningful attempt to communicate with the customer. And the customer's blind dismissal of yet another annoying banner does not constitute dishonesty.

It is completely disingenuous to frame this as though Bob walked up to Alice after lunch and asked her "Has the phone number you used for authentication changed?" and she lied and said "No".

And it seems obvious that in most cases, users that lose access to 2FA methods are not asked "has your 2FA changed?" while they still have access to the account. It is far more likely that one day their cookies are reset or google decides it's time to reauthenticate and they realize that they changed their phone number when they switched phone plans a week ago, and they hadn't thought about the consequences.