Sorry, I should have been clearer.

I do mean automated trucking. I think that development is less than 30 years away. Self-driving cars are a functioning technology now, the main hurdles (not insignificant ones) being social and legal.

Like most human-replacing technology, where the industry still exists, but is now automated ( modern car factories compared to buggy whip manufacturers), I don't expect trucking to be 100% automated, but the human factor will be reduced significantly the next 30 years.

Vehicles will still need humans to gas, service, deal with theft and breakdowns, etc. It will likely start with truckers being able to sleep during trips, still one trucker per vehicle which decreases the down time of cargo by 30%. Then there will likely be one trucker per several vehicles travelling in a convoy. Potentially there could be "truckers" based in areas that handle vehicles as they pass through, rather than travelling with them.

Of course, as the costs of trucking goes down, the attractiveness goes up, so while it may take 1/4 of the manpower to handle the same cargo, the amount of cargo will increase.

I'm estimating a 50% decrease in trucking employment in the next 30 years, even as the amount of cargo doubles.