It is interesting you said that especially as Oxfam recent study says that each minute 11 people dies of hunger while planet has 7.8bn people.
https://www.thehindu.com/news/international/oxfam-11-people-...
The inefficiency losses from production to meal (about 1/3 waste) and the unequal global distribution of food are the important factors not our ability to sustainably produce enough.
Another problem is population growth in areas that lack the necessary environmental/climate properties to sustain themselves.
Yes, I know stats, about waste, and also how half of planet undernourished, and half of planet is obese. Yes, if this is perfect world we would not have global warming, inequality, wars, we would not have extinction of animal and plant species, destruction of ecosystem... wealth would be distributed more fairly and we would already live in multiple planets. So, we do not live in that world, we live in world where people turn head on the other side when see someone on the street ask them for just a bit of food ...
Your answer is derailing the discussion to a moral debate about the worth of lifes.
By that logic why not having 40bn people, I mean there is plenty of calories, we do not have to all eat each day, every other day will do...
The entire conversation only has sense in context of life and quality of life of those people, along with all other beings in ecosystem, as idea of the entire article is benefit for having more people for the sake of economy.
There is technical level so what is maximum. Maximum amount of caries with minimum amount of calories needed to survive = 40bn. There is other side if there is one involuntary death due to starvation, there is no point of growing bigger population, as it is shitty civilization anyway and it does not deserve to exist.
Even in pure technical level calculation does not work, as we need to include all issues and loses, we cannot auto-magically say things will solve themselves.
It is necessary to include waste, and continuation of the food waste, then global warming (droughts, floods, pollution), then loss of top soil, issue with nitrogen fixation, issue with energy production, collapsing of marine life, supply chain ...