From the capitalists perspective if they forgo workers then there is no need for their goods and services.
It's odd to me that the current thought is that this idea is lost on them because they want nothing more than to get rid of workers? They want more productivity from their workers for the same or slightly less cost, which they are hoping AI can squeeze out of them. Eliminate too many workers and you have to pay the ones left more as they are now specialist, and productivity gains from AI only brings production back to when they had more workers without AI and paying less for them bringing it to about even. They gain by keeping around the same amount of workers (maybe a few less--that amount to a rounding error, but not the doom being predicted), at their current job title paying the same scraps and using AI to get more productivity out of them. And in which workers will now turn around and spend their check buying said goods at a higher cost than they were paid to make them.
Unless UBI becomes a thing, capitalists know they need workers who will buy their goods and services.