The more the better - being forced to maintain an up-to-date list of Google competitors (including some that don't keep attestation keys secure, so the bad guys

The more the better - being forced to maintain an up-to-date list of Google competitors (including some that don't keep attestation keys secure, so the bad guys will pretend to be those and you'll be forced to allow it anyway) may make some reconsider whether the feature actually brings any value.