I like how you added "by 2019-2020", as if doing the right thing 100% of the time was ever possible - let alone the goal. Of course, it isn't - Level 5 is just as good as a human. And extremely rare situation won't be handled well by a human either.
Even if companies figure out way to not get sued, its only matter of time until some very serious tragedy happens such as pregnant woman wearing same dress as color of sky crossing the road getting killed or car running in to school kids. Then there are obvious malicious usage such as modifying car sensors to fool self-driving system and purposely run in to people (cars as weapon scenario). One such thing and it could likely be the trigger for large public outcry, heavy regulations and finally game over for self-driving cars.
I think it might be more desirable to approach self-driving cars in more evolutionary fashion. We can start with self-driving only in less than 25 miles/hr scenarios such as heavy traffic OR sunny days on highways. Then we can start equiping our road networks with dedicated self-driving lanes, supportive beacons on roads and so on. Then gradually move towards make all lanes self-driving.
Why not?
Most people who are still in the media saying it can be done have a financial stake in saying those things. This doesn't make it true.
They'll get 90% there and never really figure out the other 10%.
If it proves to be difficult enough, that level will be when self driving cars are only marginally better than human drivers. That is an unlikely scenario, but it will probably stagnate at a far less perfect level than all but the most pragmatic dreamers envision.
Not before a long time.
A death is really expensive, Americans are trained to sue like crazy, a car accident is a simple case to grasp and attribute to the manufacturer who has a lot of money to pay.
The US has this "anyone can sue anyone at anytime for crazy damages" system. I'd expect any issue to quickly be brought to court and make an example out of them.
Last but not least, after the first death related to a self driving car, the second death will be on the journalists fighting for the coverage.
The first death already happened with a tesla.
Who could've thunk it?! The people who think we're going to have real Level 5 autonomous driving in 2 years (not the "we're bullshitting you with Level 5, but it's really more like Level 3.5" kind) are insane.
There's no way we're going to simulate every single condition a car could encounter anywhere on Earth and get the cars to do the "right thing" 100% of the time by 2019-2020.
I'll be impressed if they even deliver Level 4 (working perfectly only on some types of roads) by 2020. But I think even then car makers will "encounter the unexpected".
It's going to take many years to test these things. And no car makers seem to even mention how they're going to address all the security issues self-driving cars will have.