Oh even the parking lot + rain is one of those problems where the problem is not the lack of computational strength, it's the complete lack of viable ideas. There's a reason they test drive these things in Phoenix.

A crowded parking lot of a mall can be challenging for a beginner human driver, it's an absolute AI nightmare as there can be totally unexpectedly moving cars and pedestrians at any place and time. And then {rain,fog,snow} messes with LIDAR and you have a half blind (at best) system trying to navigate an extremely challenging environment.

It will only work when all cars have a sensor set and can communicate effectively to cover the entire area. I don't see how it can possible work if you throw human drivers into the mix.