If you enable Security Keys, does this mean you can no longer use iCloud for Windows or Apple TV or any other device that doesn't support Security Keys?
What doesn't work with Security Keys for Apple ID
* You can't sign in to iCloud for Windows.
* You can't sign in to older devices that can't be updated to a software version that supports security keys.
* Child accounts and Managed Apple IDs aren't supported.
* Apple Watches that are paired with a family member's iPhone aren't supported. To use security keys, first set up your watch with your own iPhone.
Does this mean there is no alternative login presented when using a device that doesn't support Security Keys?