I am not sure how you define monocropping, and so I will write what I think it is.
By “monocropping”, I am talking about planting a single cash crop on a plot of land. A farm may operate multiple crops, each on its own field. They might rotate crops with cover. Some might even interplant crops in rows, or even between plants (as cover). Each field is intended to grow and harvest a single cash crop. You don’t even want to different varieties of the same species close together because you want to ensure a consistent produce. Many restaurants demand consistency (easier to consistently produce dishes when ingredients are of consistent size and quality), and consumers have been conditioned to take a few varieties as representative. (Example: many consumers think of Roma tomatoes when they think of “tomato”).
The combines are designed to till, sow, and harvest in generally linear rows, for a single type of crop. The field is plowed in a way to be level, so that watering can be as uniform as possible. Soil amendments, such as fertilizer, is relatively simple to apply.
So as an example, an old Native American practice called the Three Sisters: corn, squash, and beans, can be planted together. These three crops, when planted together, includes a plant that will fix nitrogen (beans), as well as a ground cover (squash) that help retain moisture. The corn stalk functions as a trellise for the beans, and help shade it. Beans can be harvested early in the season, corn and squash later in the season, with squashes working well as a dense store of nutritional energy that will last through the winter. It also happens that there are lots of culinary dishes that also combines these three plants.
I know of no industrial farming practices or equipment that practices the Three Sister. Driving a harvesting tractor through there will destroy the squash, and probably the beans too.
There are other combinations such as, tomatoes and basil; strawberries and asparagus.
When I use companion planting in my garden, I noticed a few things. First, harvesting is more difficult. You have to be able to identify each plant. I had to look through the different canopy layers to see what is going on. But it was also my first attempt, and I think I can design it a lot better.
When done this way, yield are not as good for any single crop (if they don’t synergize on nitrogen fixing). But I also wonder if the total crop output across all harvestable plants are better.
That is just for annual crops. There is a similar practice that can done for perennial crops. This is what those “food gardens” mentioned in that article, though they are usually called “food forests” by enthusists.
One of the things about this method of farming is that it is intended to decentralize food production, letting the bulk of the food production be local, in order to reduce transportation. You can then grow varieties that taste better and are more nutritionally dense, instead of being bred for staying edible and transported by refrigeration. (I am looking at you, roma tomatoes and hothouse tomatoes).
During the years of international sanction, Cuba had to develop self-sufficiency with use of very little fertilizer (no oil imports), no gasoline driven farm equipment (no oil), and as little motorized transportation as possible. They used a variety of methods, some drawn from modern science and some drawn from older farming practices; but whatever it was, they could not simply use pesticides, fertilizers, or refrigeration.
https://www.architectural-review.com/essays/cubas-urban-farm...
https://www.smartcitiesdive.com/ex/sustainablecitiescollecti...