Yep, if we can get self driving cars and people are actually willing to share that space with strangers it will be a big win for transportation efficiency.
However at the same time we should be investing in density and figuring out ways to make that work. Urban sprawl is massively innefficient by it's nature.
The reality of cars (single occupant) is lower-bandwidth than the fantasy of bikes (lots of bikes traveling like a school of fish). I agree with that.
But if you compare the reality of both, cars are still massively higher throughput in the US.
And if you compare the fantasy of both (fully-loaded cars vs. herds of bikes), then cars would again be higher-bandwidth.