This is a perfectly reasonable intuition – that there will be large net loss of jobs as trucks are automated – but we should not mistake the intuition for evidence. There is a long history of believing that massive job losses are imminent due to technological advance.
The problem with mistaking this fear for a fact is that it often leads to an incorrect intervention. (I call this a WMD argument.)
We’d be much better served with much greater caution about what is actually, observably, measurably true. In this case, we’d have to discover the yet-unfound correlation between technical advance and employment rate.