A study predicts that 40% of current work jobs in Australia will be eliminated by automation within two decades.

It is hard to be accurate in such predictions. Perhaps it will be only 30%, or perhaps as much as 50%.

Things are likely to be similar in the US.

It will surely be possible to replace the lost employment with other employment, if we don't care how little the new jobs pay. There is no assurance, however, that so many millions of people could find employment that will pay for food and shelter.

Therefore, we will have some mixture of rejection of automation, welfare payments such as a basic income, and massive suffering. The only question is how much of each.

I'm against the last one. Either of the first two is ok.