I hope you're right. I could see that happening in warmer climates. But what about when landmarks and points of reference are covered in snow? GPS is not accurate enough to be used as a sole reference, you need a visual/LIDAR reference to back it up.
The system will have to work in 100% of circumstances before laws will be changed to allow for driverless cars. I could see that happening in 20 years, but I really doubt it'll be on the streets in 5 years like Elon Musk and others have suggested.
Construction alone is going to make it extremely difficult, unless there is a system such that the cars know where construction is taking place and actively avoid those routes, but that is not always known.
The system will have to work in 100% of circumstances before laws will be changed to allow for driverless cars. I could see that happening in 20 years, but I really doubt it'll be on the streets in 5 years like Elon Musk and others have suggested.