tl/dr:

when economists say "you don't have to be afraid of technological progress, you will still get to work"
tell them, that you don't even *want* to work and that they shall pay you a fucking basic income or give you some of the machines. Then hit them with a brick.

Giving the fruits of machine production to the rest of the population is actually good for the economy, because it increases spending capacity.

The recurring crisis of capitalism is one of ppl not buying stuff - overproduction. enabling ppl to buy the fruits accomplishes 2 things:
1) markets are animated,
2) workers are dependent on the owners of the mashines.

But it has to happen via hidden subsidies, a social state, for ppl not to wonder why they can't have the machines.

to do unnecessary labour instead, to afford the fruits of the machines which do the necessary labour, then we are fucking pissed.

unemployment doesn't rise after technological progress because workers are forced to work unnecessary bullshit instead, so economic growth can happen and the means of production stay in the hands of the capitalists.