Hmm...we can't find this setting yet, but we'll keep checking. Feel free to contact us for help.
Looks like you're signed in with a Gmail account. Please try again with your account that you use to access Google Admin.
If this policy is set to true or not configured, Google ChromeOS will show existing users on the login screen and allow to pick one.
If this policy is set to false, Google ChromeOS will not show existing users on the login screen. The normal sign-in screen (prompting for the user email and password or phone) or the SAML interstitial screen (if enabled via the LoginAuthenticationBehavior policy) will be shown, unless a Managed Session is configured. When a Managed Session is configured, only the Managed Session accounts will be shown, allowing to pick one of them.
Note that this policy does not affect whether the device keeps or discards the local user data.