Reclaimed By Nature

But there are no better modes of transport than cars. They are literally the most used vehicles on earth. This means they have topped every other form so far.

This is an appeal to popularity. Something being popular does not make it the best or good. Bikes are also insanely popular - with around ⅔ as many bikes as cars world wide. Car usage also varies highly from city to city. Unsurprisingly those that have good viable alternatives have much less car usage. Build lots of roads you get lots of cars.

Self driving is not a solution to the massive inefficiency of cars; it's likely to make it worse. Improving the quality of a mode of transit generally results in increased usage - this is known as induced demand. Not needing a license nor having to pay attention means more people will opt for the car instead of alternatives, resulting in more congestion.

They're also unlikely to reduce the number of cars per person. Assuming self driving cars are cheaper than the current situation why would people voluntarily sit next to a stranger in a locked metal box when - for less than they were paying before - they could not do that. They'd also be trading off journey time - the number one thing people care about in regards to transit.

So more people would use cars, but cars are parked unused 95% of the time, isn't there efficiency to be gained there? Yes, most likely. But the thing to remember is the majority of cars are on the road at the same time during peak hours. Even if you double the efficiency here you'd at best be reducing the parking needed by 5%.

You are right though in regards to cars not going anywhere. They are a valuable mode of transportation, especially in rural areas. Hopefully self driving won't make car dependence even worse.