> Are you seriously suggesting that it will be a trivial thing for farms that currently rely on manual labor to switch to large-scale mechanized practices?
Of course not. I'm suggesting the opposite: That they have no chance of competing with manual farm labor, so there's no point in trying.
> So I don't see how they can avoid a process similar to what occurred for western farmers starting ~1900.
I don't see how a development process that may have happened in the West over a hundred years ago, under completely different circumstances, can be repeated in Africa in 2019. That's literally the question I am posing: How could this kind of development possibly work through farming?
> They don't need to be competitive on a global scale, they need to find a profitable niche in their own countries.
You can't ignore the global market. The whole reason why many farmers can't make a living in Africa is because foreign produce is cheaper, due to automation. So you would have to restrict foreign produce, raising its prices and therefore making everyone poorer (except the farmers).
> Additionally, increasing employment seems far preferable; likely developing local economies is the best way to increase standards of living rather than relying on foreign aid.
Developing local economies is fine, doing it through farming is completely misguided. In farming, a massive amount of labor can be automated away and will be automated away if economic development actually takes place, so any employment here would be temporary at best.
Instead of farming, let's take the manufacturing of clothes. Some of it can be automated away, but not necessarily to the point to make 99% of workers redundant. As a result, you can see many emerging economies producing clothes for international markets.
> Also note that there are many crops even in the US that heavily rely on hand labor (typically fruit/vegetables). While it may not be feasible to compete with imported grains, I can certainly see how local farmers could effectively compete for these crops- which would likely also increase the diversity of foods avaliable in local markets.
I did note as much, specialized farming may well be a profitable niche for exporting. Except those misguided western do-gooders aren't helping them build supply chains to western markets for valuable produce, they're telling them that raising rats and snails for the domestic market is totally the right thing to do for economic development. Utter nonsense!
> How is it anything but a net positive for them to develop local industries; the increased economic output is likely to improve the entire local economies and doesn't rely on foreign aid (which can suppress long-term economic development).
Because of comparative advantage. Making domestic farming sustainable would require protectionism. We figured out hundreds of years ago that protectionism doesn't work and effectively makes everyone poorer, yet somehow it's still popular among politicians (like Mr. Trump).