With Security Keys — available in macOS Ventura — users have the choice to make use of third-party hardware security keys to enhance the protection provided by two-factor authentication. Apple says this feature is designed for users who, often due to their public profile, face concerted threats to their online accounts, such as celebrities, journalists, and members of government.
Apple says that for users who opt in, Security Keys strengthens Apple’s two-factor authentication by requiring a hardware security key as one of the two factors. This takes our two-factor authentication even further, preventing even an advanced attacker from obtaining a user’s second factor in a phishing scam.
To set up Security keys with your account, you’ll need to have at least two security keys (you can have up to six). This a bit of an inconvenience, but it does mean that you’ll have a backup should you lose your primary key so won’t be locked out of your account.