I think we will see autonomous cars on our roads before this happens. Even so there will be humans watching and at the controls incase they need to take over. When lots of money is at play I doubt anyone would risk it on machines doing everything.
Time frame? 15-20 years many industries will be autonomous. But then where will the people work? No work no money no buy stuff. There is kind of a symbiotic relationship with consumers and manufacturers right now this automation may screw that up.
Yes i agree autonomous cars will definitely be on the roads, Elon Musk has teased that level 3 autonomy is mostly finished and needs small refinements before implementation in all Tesla vehicles before the end of this year.
Your second point is something I don't understand, statistical studies have shown autonomous systems, even now, are far better at processing risk and reacting to it than humans. Having a human 'watching' is pointless. In the case of total system failure the autonomous system would be programmed to simply pull over and wait for assistance. Management is based on statistical evidence, which is why firms today implement as much autonomy as technology of today allows for exactly the reason of limiting risk. The biggest risk to any system is the unpredictability of humans.
As for your point with jobs, I do agree that in the short run job loss may be a problem. But you have to realize this type of thing has been happening for centuries. Not too long ago most of the population was required o work in agriculture in order to feed ourselves. As agriculture became more efficient people panicked about jobs being lost. Instead other industries grew to provide employment. firstly their is the direct employment of industries that develop and service the autonomous systems. Secondly autonomy will drive down the cost of goods, meaning consumers will have more disposable income to spend elsewhere,for example service industries or entertainment industries.
Interesting topic, I agree we will see autonomous vehicles on the roads during the next few years and industries like Uber will co-exist with the death of taxi licenses as an industry in the intermin period before autonomous transportation. The question is how many people will trust automation over human interaction even the ultra rich would likely keep a chauffeur around until retirement versus a self-driving car.
In regards to job loss the issue is finding a transferable industry where people's skills can be applied, for drivers that will involve machinery operations and other areas where autonomous machines still would need time to develop such as construction winches etc, although the part's that are not automated do go abroad example mexico hence their are trade battles about labor.
I believe santaclaws was talking about the associated industries and the impact on their jobs that automation impacts. In your case the main focus was on the driver of the vehicle being replaced without consideration for the part manufacturers/oil and lube changers/ mechanics/ restaurants that driver visits and other side industries that see a decreasing demand and possibly shutdown in the long run due to a decrease in the total number of users demanding their services.
Not that it would disappear entirely of course there will still be demand as long as private vehicles exist but the amount of parts to fix a car and the people who have expertise associated with different brands and repairs will fade away, sort of like the skill-set of people who design cars and airplanes all their lives retiring less skilled/experienced people will replace them in the workforce.
So your presumption that consumers will have more disposable income assumes that the individuals are fluid enough to succeed in transferring their skill-set elsewhere or finding another low cost labor industry if their skills are insufficient to code a computer mainframe or network from scratch. So in a sense your right the biggest risk is the unpredictability of humans will they be able to succeed in another industry or enter a poverty cycle because they cannot find another job and that is where job subsidization and transition training is required aka government interference to reduce the contagion effects which tend to be left unmitigated in modern society.
The market presumes it is a self correcting mechanism with no leaks cough since it's seems like such a pain to fix it a classical argument ^^. But is it Elon Musk's job to fix it nope it's up to state actors at some point to patch the plumbing.
http://www.raybromley.com/notes/ADASequiMove2.html