Whoopsy:

Quantum computing is orders of magnitude faster than traditional computing, Tesla was taunting they had the fastest automotive computing before, well that title is no more.

And with quantum computing resolving traffic congestion avoidance, there is no need for autonomous driving, that technology was invented just so people aren't driving and stuck in traffic in the first place. 

But I mean, Tesla could play catch up and use quantum computer in their cars to boost their autonomous driving ability. 

I get quantum computing. I just don’t get how knowing about congestion makes my drive autonomous?  Why would easing congestion mean cars can drive themselves?  One gives you information about traffic the other lets you enjoy the ride while doing nothing. Of course the two would work well together. An autonomous system may also be better are feeding data to the congestion system so that would help.  
It just means you get there a little quicker. I never see any traffic jams to work. Ever. This would not help me at all. 
Do take a peek at the tech demo of the hardware they use, it is informative. It may help the discussion so we don’t confuse traffic congestion with self driving. 
Given the state of quantum computing I doubt that they would be economically effective in cars. When VW puts one in a car let me know. Tesla goes so far as to take the energy consumption and heat from the computers into account. They optimize the software and hardware for this. They have all the hardware and processor speed for the task of self driving right now. I would bet their AI would be the first to centrally use quantum computing to teach more self driving situations to the collective but in a car or each car would be massive overkill given the speed of their current processors for the job. 
So when when VW installs the first quantum computer to perfect self driving let me know. Until then it is just a central congestion tracker.  It is not being used by all cars along the way to adapt traffic patterns or anything like that. Sounds like fancy navigation.only