Governments are not ready to admit the fact of the Earth's overpopulation.
1. Corruption. I saw this first hand. For every $1M sent into Africa, a very large proportion is confiscated by tribes, gangs, militia, and the government. You can send all the excess food in the world, but there are thousands of people between production and the hungry person who is eager to violently steal it.
2. Africa's population is booming. Thanks, in part, to food aid. Half of Nigeria doesn't have access to toilets. 40% doesn't have electricity. 25% doesn't have running water. Their fertility rate is 5.2 children per woman. We are unintentionally propping up a future catastrophe.
3. Food aid has destroyed local farming and food production. Locals cannot compete with free.
4. Equitable allocation is impossible. There is no hunger score above each person's head. Even if there were, there is no supply chain anywhere in the world which can reliably and repeatedly deliver the necessary food aid to each person in the deepest African jungles. We rely on distribution hubs which are sparse, poorly run, intermittent, and subject to temperature and humidity extremes. This means food perishes fast unless it is ultra processed and packed for durability. Basically army rations. Even those expire after some time. Meaning we can't just take the Colombian bananas and send them around the world. Only certain foods work, and they need to undergo expensive and specialised processing. This entire supply chain is far more expensive than you can imagine.
I will close with my own opinion. While the world could sustain a higher population, it is clear to me that it will result in diminishing quality of life for everyone. Crowded conditions and increasing scarcity are not aspirational goals for humanity.
I'm choosing to ignore a lot of the problems with people from disparate backgrounds living together, people not actually wanting to leave where they live, people not wanting to share freely available resources, etc. Those are very hard to solve problems.
I'm only saying that over-population is not the cause of resource problems. If we can solve the other problems then a lack of resources stops being a problem, which proves population size is not the root cause.
New York doesn't magically receive food. New York is a large net recipient of food imports. It produces value to society and exchanges some of that value for food farmed by others. The U.S. (and most of the West) is structured in such a way that productivity per capita is high, and it means everyone in the food supply chain can live a reasonable lifestyle with enough food. Most African nations do not structure their society this way. It's not an accident. This is the way they choose to live. I grew up in Africa and I'm happy to explain the many ways in which American and African cultures differ. For example, corruption isn't corruption in most of Africa. It's good manners. Gift giving has been happening in tribes for thousands of years. In business it is a common courtesy to provide a gift during negotiations. Of course the person with the largest gift is the most generous and the nicest person, so of course they get the contract. This is a fundamental difference in our cultural and social understanding of what is right and wrong.
What you appear to be exercising is a typical Western hubris: "if we can just get the savages to live with us, they would see the light and live like we do." This assumes that everyone want to adopt your values and way of living. They don't. The reason there isn't much food in Africa (relative to the population size) is not by chance. They live on some of the most fertile land in the world. Africa should be the breadbasket of the world. The issue is that they don't like the way you live and don't want to live that way. Any kind of mass migration strategy would merely result in lots of hungry people in America.
You chose to ignore all that, and argue against the point I explicitly didn't make. Congratulations on winning that argument. Your prize is a huge straw man.
Gangs can only want so many machine tools and steel plates, if you don't use them they are just in the way. But people who do use them and learn how to do it well become immensely valuable and beneficial to all.
Gangs don't use the farm equipment. They steal it and sell it. They will steal any equipment they can and there is an unlimited appetite for equipment on the black market. Especially in China and Southeast Asia.
One part of the problem could be sending them super cheap/crappy tools because it seems like a better value per dollar and also the constraints of total funding. Sometimes maybe getting ripped off by foreign suppliers because there is a LOT of really crappy steel out there disguised as tools and engines that are all but useless. But tractors and tools that break down that easily are a complete waste of money and time to people who will barely get to use them before they stop working and they likely are right that it is junk. We have the technology to make a tractor that is robust enough that you wouldn't expect any maintenance for years if not a decade and minimal even at that point. I definitely don't see many decent manual CNC machines and lathes or other machine tools getting sent over in numbers enough.
Of course a lot of this still ultimately comes down to cost which is not an easy issue to deal with.
Water is not scarce in general, just yet. It scarce where population is exploding.
Unless the new people are used as an army to take the needed resources from others...
If the local reservoirs were not already at capacity, or had much more redundancy, these events would have been much easier to manage. Fewer people in high risk areas would in fact reduce the risks of water scarcity.
Regarding water specifically, we now have multiple desalination projects of 1MM m^3/day, enough to support a city of 4MM people. They are expensive, but getting cheaper, and real (rich) polities in the Middle East are relying on them.
For example for Algeria: "available resources dropping from 1500 \(m^{3}\)/capita/year in 1962 to 500 \(m^{3}\)/capita/year by 2016, far below the 1000 \(m^{3}\) threshold set by the World Bank"
the main factor is a region overpopulation.