If this setting is enabled, users will be allowed to set up their devices to sync SMS messages between their phones and Chromebooks. Note that if this policy is allowed, users must explicitly opt into this feature by completing a setup flow. Once the setup flow is complete, users will be able to send and receive SMS messages on their Chromebooks.
If this setting is disabled, users will not be allowed to set up SMS syncing.
If this policy is left not set, the default is not allowed for managed users and allowed for non-managed users.