For context: this is largely based on the entire "bullshit jobs" concept by David Graeber, which has actually been shown in research to be right. (Graeber himself was surprised by how right he was, back when he still lived. Because he assumed it was maybe like 10 to 15% of people working, not 30%.)
But I think it is also quite obvious if you logically think about it.
Think about what work is actually essential. We technically know this right now very well - because the lockdown was not that long ago.
Jobs related to food production and food logistics
Jobs related to water management
Jobs related to waste management
Jobs related to infrastructure construction and maintanance
Jobs related to clothing production to a certain extend
Some jobs related to grooming
Food production and logisitics is technically already massively automated. Yes, this does not change that especially food production, together with construction and textile work are also the areas of jobs involving among the most exploitation and slave work to this day. But still: the amount of man-hours involved in any food production these days is tiny to the amount it took just 100 years ago, let alone 300 years ago, when the vast majority of any work done in total was in food production.
Same with water management. And waste management, as well. While waste management is a bigger problem than it ever was, it still is automated for the most part.
Now, in terms of infrastructure and maintenance it is a bit more complicated and highly varied. Like, yes, it is so much more automated, but also some parts do badly when automated so... still, while this tends to be the biggest area of man hours needed in terms of the essentials today, outside of care work... it is still less.
Clothing is not as automated as you think it is. This is still mostly manual labor that does get underpaid - but ironically speaking if it was done better less of it would need to be done (reminder that most clothes these days end in landfills).
Education, care, and personal hygiene is the areas that indeed you cannot automate a whole lot. But it still is not... even if more people worked in those areas than they are doing today (you know, given that those areas are currently mostly understaffed), it still would not mean every human around needs to work a 40 hours a week job.
I mean, just look at what jobs people these days are actually working. So much work is just some dead end office work and stuff along those lines.
I am talking about this because I see so much fearmongering among people because "well, if we did Solarpunk (or any more anarchist or communist way of organizing society) what about the artists, because EVERYONE WOULD NEED TO DO ACTUAL WORK", when the last thing could not be further from the truth. That is without going into how arguably indeed art is more essential at the very least than the work of most people working in banks and shit. But it really is not a big issue. We can automate so much of the necessary work by now that we actually can afford for way more people doing professional art than any other human generation could.
