Yeah but DLS would be a significant downgrade for many people, who already fight the suggestion to only eat meat six days a week tooth and nail.

https://pmc.ncbi.nlm.nih.gov/articles/PMC6013539/

https://pmc.ncbi.nlm.nih.gov/articles/PMC10537420/

https://pubs.acs.org/doi/suppl/10.1021/acs.est.3c03957/suppl_file/es3c03957_si_001.pdf

Things that count as DLS:

• 10 m² of personal living space + 20 m² for every 4 ppl as bathroom / kitchen
• 2100 kcal/day
• 1400 kWh/year, but this already includes public services (education/healthcare)
• 1 washing machine per 20 ppl
• 2.4 kg clothing / year
• wear tops for three days and bottoms for 15 days without washing
• 1 laptop per 4 people with a yearly power consumption of 62 kWh. (bizzarely they talk about an 800 MHz computer and seem to confuse HDD and RAM). If your gaming computer used 400 W you could use it for 150 hr/year.

This is one of the things that pisses me off about the Star Trek "fans" who point to the Replicator tech (which wasn't introduced until the Next Generation series) as the reason humanity was able to end scarcity. No, it absolutely was not what ended scarcity in the Star Trek universe. What ended scarcity was the absolute end of capitalism. We have now and have had for over a century, the capability to end world hunger and provide housing for every man woman and child on the planet. We don't do it because it would remove the overinflated value of those things as well as the obscene wealth of the rich.

Why can’t we just have fewer people too? Instead of finding ways to support 50 billion people, how about we have good birth control facilities, education, and economies not based on constant never ending growth? The reality is unending growth WILL end whether people like it or not- wouldn’t it be better to do it on our own terms rather than in a global catastrophe?

Reading the study I get the following remarks:

Living space, not great. 60m2 for a 4 person family. That's tight. I live alone in a 90m2 house and I could use more space, do they want me to live in a 15m2 house or do they want to force to share living space? Sorry but I won't compromise there. I prefer people having less children that me having to live as ants in a colony.

That is just a personal pick with the DLS minimum requirements chosen.

But still forgetting that. The reasoning is extremely faulty. Most of their argumentation heavy lifting is just relied to Millward-Hopkins (2022) paper establishing that 14.7 GJ per person anually is enough. That paper is just a work of fantasy. For reference, and taking the same paper numbers. Current energy usage (with all the exiting poverty) is 80 GJ/cap. Paleolitic use of energy was 5 GJ. Author is proposing that we could live ok with just triple paleolitic energy. That paper just oversees a lot of what people need to live in a function society to get completely irrational numbers on what energy cap we could assume to produce a good life.

Then on materials used. The paper assumes all the world shifting to vegetarian diet, everyone living on multiresidential buildings, somehow wood as the main building material (I don't know how they even reconcile that with multiresidential buildings...). And half of cars usage shifting to public transport How to achieve this in rural areas it's not mentioned at all).

A big notice needs to be done that both papers what are actually doing is basically taking China economy (greatly praised in the introduction) and assuming that all the world should live like that. And yes, probably the world could have 30 billion inhabitants if we accept to be all like China, who would we export to achieve that economic model if we all have a export based economy? who knows, probably the martians. And even then, while a lot of "ticks" on what a decent level of life quality apparently seems to be ticked, many people in western countries would not consider that quality life, but a very restrictive and deprived life standard.

I'm still on the boat the people having less children is a better approach to great lives without destroying the planet. At some point a cap on world population need to be made, it really add that much that the cap is 30 billion instead of maybe 5 billion? It's certainly not a cap in the number of social iterations a person can have, but numbers give for plenty of friends. And at the end it's not even a cap on "how many children" can people have, as once the cap is reach the number of children will be needed to cap the same to achieve stability. It's just a cap on "when people can still be having lots of kids". Boomer approach to "let's have children now" and expect that my kids won't want to have as many children as I have now.

Also another big pick I have with the article is that it blames the current level of inefficiency to private jets, suvs, and industrial meat. But instead of making the rational approach of taking thise appart from the current economy and calculate what the results will be. Parts from zero building the requirements out of their list. Making the previous complaint about those luxury items out of place completely. On a personal note I would reduce or completely eliminate many of those listed "super luxury" items. But I have the feel (just a feel because neither me not the author have studied this) that the results of global energy and material usage won't drop that much, certainly not at the levels proposed by the authors with their approach.

Technically, earth's land area is big enough to sustain around 24 billion people. Consider this diagram:

It shows that we're using around 50% of all habitable land for agriculture. Most of the land that we aren't using is either high up in the mountains (where terrain isn't flat and you can't use heavy machinery) or in the tropical regions on Earth close to the equator (south america, central africa, indonesia), or in areas where it's too cold for agriculture (sibiria, canada). so you can't really use more agricultural land than we're already using without cutting down the rainforest.

In the diagram it also says that we're using only 23% of agricultural land for crops which produce 83% of all calories. If we used close to 100% of agricultural land for crops, it would produce approximately 320% of calories currently being produced, so yes, we could feed 3x the population this way.

However, it must be noted that there's significant fluctuation in food production per km², for example due to volcanic eruptions. So it's better to leave a certain buffer to the maximum amount of people you could feed in one year, because food shortages in another year would otherwise lead to bad famines.

Does this assume instant, frictionless transportation of goods?

Most of the 8 billon people are living in the third world and which less resources waste, most recources a wasted by less than 10% of the world population.

Oh, I know!

wE sHoULd KiLl HalF oF ThEm

Define 'decent living standards'.

The design choices of people who make memes out of their political opinions are so random and funny to me sometimes. Like why is one of them a Russian gopnik? Why is the other one a blushing gamer femboy who paints his nails??

But image if we can provide so much for 8.5 billion, it means we can provid double for 4 billion. There is no reasonable excuse to keep increasing the human population.

I agree that we can support everyone on earth if we change our social, economic, and political systems.

I also think it is good that voluntary population decline is already happening and seems likely to continue in many industrialized nations.