> Do you think banks are using attestation gratuitously?
What I'm claiming is that banks have the freedom of offering their customers 2FA other than smartphone apps.
> Do you even have a phone that does not support hardware attestation or is all this posturing about something hypothetical?
All the phones I own, including my daily driver, run some flavor of Debian. None of them support hardware attestation.
I'm in Europe, bound by PSD2, and own a couple of cheap, certified chip-and-TAN devices so I can do banking.