Your main point is correct, but take in account this, too: So far technology has replaced or created new jobs requiring not much more in terms of skills. To make a very simple example: cars were not extremely more difficult to drive than a cart. And way easier (less physical strength required, for example) than riding a horse.

So if someone was intellectually capable of learning to drive a cart, they could probably manage a truck. People leaving their farm (thanks to increased mechanization of farm labor) could move to the city and work in a plant or in a blue collar job with little training.

Of course, advances in science and technology also created whole new jobs that required a lot of study (I dunno... Engineer, Chemist) but it was not like everyone who was made redundant as a cart driver or a farmer would move to the nearest city and become a scientist.

So the problem seems to be this: assume that half of the truckers will be made redundant in 10 years. How many of them will succesfully "pivot" in something else, like truck AI programmer? 1 in 1000? Of course, they could become ... truck mechanics... but, wait... we already had mechanics working on human-driven trucks, and the fact that some trucks are now autonomous will not require an large amount of extra repair shops to cater for them. So, what will the not-truck-driver-anymore guys do?