All of transportation cannot be shared or multi-passenger because some trips are to places where nobody else is going. Perhaps in dense cities, which will take at least 50 years to rebuild in a walkable way in the US. But people will still want to enjoy natural places - lakes, rivers, mountains, deserts, forests, and snow, and there won’t always be rails built to access those places. Electric mountain bikes with a 500 mile range maybe? Personal transportation will always be around.