I think this game could be made so much better if there were policies built in the base game or in DLC (I don't know which one has this, if any) where car use would be penalized or made extra difficult (something like in Singapore in real life for instance).
While this may make the game a little too easy for some, for others, the car dependency that's implemented in the game makes it hard for those who want to recreate a European-based city (or some other region-based city famed for excellent public transport), and while this can be done without mods, those who want to play a game and earn achievements without the use of any mods, will have quite a rewarding experience in creating a city in which car-restricted or car-free travel can be made possible within the game's constraints.
While this may make the game a little too easy for some, for others, the car dependency that's implemented in the game makes it hard for those who want to recreate a European-based city (or some other region-based city famed for excellent public transport), and while this can be done without mods, those who want to play a game and earn achievements without the use of any mods, will have quite a rewarding experience in creating a city in which car-restricted or car-free travel can be made possible within the game's constraints.