In most servers, you can go around and ask; Most laborers such as Miners, or Lumberjacks will tell you that they usually forage for food to keep up with the demands of a server for their profession. Even with 5-10 players, at least half of them will catch and consume charred fish for calories alone, regardless of their skill point gain or profession. Later on, when their role is maxed, they'll turn to food production for better rates/quality for themselves. And in turn, become less dependant on the food production roles in the world. Aka the Farmer.
I've played for many, many years, and farming/food production has been my favorite role. In fact one I've only played willingly. Food runs the server, without it, you can't play/do things. It's impossible for one person to feed many, with multiple farmers sure.. you can grow/harvest/forage enough food for a group but in no way is it quality food.
A while back the Farming/Crop system completely changed to what it is today, and it completely stunted the Farmer and his/her crops. In my honest opinion, the change is bullshit. I've even commented on it once awhile back on the forums here, how I find it utterly nonsense that a Farmer cannot plant a 20x30 field without 1/3rd+ of his crops dying because they're overcrowded. If the game was trying to go for an Eco-Realism, the human population would have died out by now based on these rules. Obviously none of the developers have a green thumb, let alone a history of even putting a seed in dirt before, or dare I say... seen a farm.
I grew up with fields of wheat, corn and beets around me. As far as the eye can see. Overcrowding doesn't kill a plant. It stunts the quantity. I encourage our devs to plant 2 rows of vegetables in their office, literally any. Corn, Beets, Carrots, Anything. Buy a grow lamp off Amazon, it's like 50 bucks. One row, plant the 10-20 seeds as directed in length/depth by the package, and the second row.. plant them a little closer together, so 15-25 seeds. Now you can go ahead, and do this, wait the 30-65 days depending on the seed, and show us your findings. Because this system is rubbish.
The idea behind the new system is that you use a world-layer to find a population-viable plot of land for a plant. Currently, I live in a good spot for Beets and Wheat. So you till the land, fertilize it if need be, and plop your seed in the dirt. Wait a day, and harvest. Crop rotation is certainly needed unless you plan on fertilizing before every crop, then repeat. Seems simple enough, as long as you find the right plot of land. But, if you plant too many.. Your crops become overcrowded, and die.
So even if you have PERFECT land for Wheat, it still dies. Funny, it's perfect for wheat.. each block, 20 long by 30 wide, but not perfect enough to actually grow your crops. This doesn't make sense. Again, over population might effect your Aerogarden, but not when each block is 1 meter squared. 1 Meter of ground is more than enough to grow 1 wheat seed. In fact, you could throw in 8 more seeds in that block and still have a good harvest depending on your weather.
1 Block, 1 Meter squared, 1 seed directly in the middle of that block. That means the next seed is 1 meter away... yet, it becomes over crowded.
As for what the OP said, about small backyard farm plots 5x5, and people building next to you.. I don't think the system works very well for players building a farm in a town.