Autonomous Vehicles (AV) are the future evolution of Land Transportation Systems (LTS). They promise an improvement in road safety. However, safety requirements stay a big challenge for their development. The literature presents a lack of insight on the way LTS safety requirements will evolve. This paper proposes an analysis method of LTS safety requirements evolution toward AV. The ASIL metric is used to evaluate the safety criticality. The application on two case studies, the steering by wire and platooning systems, results in a better understanding and characterization of this evolution.