Yes, the Digital Workspace supports Single Sign-On with the Identity Service. See the Single Sign On Guide v2 (ACS 7.3+) section of the Identity Service documentation for more details.
The Digital Workspace does not support SAML Single Sign-On (SSO) for Alfresco Content Services. Users can login with their credentials using basic authentication, but SAML authentication must not be enforced.
See the SAML Module for Alfresco Content Services documentation for more information.