And footnote 2 on that page says:
2 DRIVE PILOT is an SAE Level 3 (conditional automated driving) system: the automated driving function takes over certain driving tasks. However, a fallback-ready user is still required. The fallback-ready user must be ready to take control of the vehicle at all times when prompted by the vehicle. Availability and use of DRIVE PILOT on freeways depends on options, compatible wireless networks, countries, states and relevant laws. Service subject to change at any time without notice. Mercedes me connect Terms of Use apply. Please refer to the Operator's Manual for additional instructions and limitations.