Technical innovation increases the productivity of labor in industry. If production shouldn’t be wasteful, there needs to be a reduction in workers. Where do all these workers go if there’s no unemployment? In a capitalist economy the workers are left to die on the streets but in a socialist economy they need to get a job again, right? Does the state take the burden of cost of reeducating these workers to enter another field and factor this into calculations when introducing new technology?
It’s a little difficult to answer specifically without an example socialist country, so I’ll keep it theoretical.
While capitalism is happy with the result of implementing new technology (high unemployment), it’s not inevitable. Even under capitalism, the state creates jobs, many of which don’t really need to exist. The state has to ‘make’ money, too, or there’s nothing to circulate, broadly speaking. Which means that whatever happens, the state has the ‘burden’ of giving out money to someone. In capitalism, it’s to the bourgeoisie, to public workers, and to the pensioners and the poorest in pensions and welfare. It doesn’t have to be balanced in this way.
It’s similar in quasi-public workplaces (like universities) and private businesses, where jobs can apparently be created out of thin air for someone’s niece or nephew. The money is magically ‘found’. There’s a lot of creative accounting! The same thing can happen under socialism, determined by the state, to reach full employment.
Additionally, under capitalism, there’s an incentive to pay existing workers overtime rather than get more workers. If I do overtime, I either don’t get paid for it or I get paid a bit more, by the hour. If the take the overtime off my and everyone in my area and give it to someone else to fill up a new person’s schedule, the employer needs to pay: for another computer, internet access, a chair, a desk, space, a vehicle, health insurance, etc. One more worker costs a lot more than just their salary. That’s unacceptable to capitalists.
Socialists might be more willing to pay the price, knowing that producing the extra equipment for the new worker (averaged by all the new workers across society) will need to be made by someone, creating more jobs. It’s a feedback loop. It’s not necessarily more costly overall. But it requires redistributing some wealth.
If we paid the senior management team slightly less and stopped paying the shareholders, at many companies you could double the number of workers and keep everyone full time.
Alternatively, you can shorten the working day to increase employment. If you have 100 workers doing an average 40 hours a week, that’s 4000 working hours/week to keep the company doing what it’s doing. That could become 160 workers doing 25 hours/week, for example. The wages could be the same or lower if things were set up right. (E.g. if rent was capped or healthcare and higher education were provided by the state, so people didn’t need to factor those costs into their savings, etc.)
These are just some ideas. Quite Keynesian, too, so not even that radical, really.