Absolutley, I do not discourage individuals from enjoying four chickens or something, but don't get confused about the time, effort or cost. Often you will be better off just going to the farmer's market.
Discussion
and thats how we end up with centralized food production all over again.
Better to build scale in the community as an aggregate. I remember there was a hurricane once when I was a kid that flooded large swathes of farm land. We did what we could for the farmers near our land and helped with bridge repairs etc.
The first thing over the bridge was truckloads of farmers from districts that had been spared. they prought supplies and food and fuel to get the place functioning again way faster than waiting for the government to show up. This is the resilience of a local but distributed food network.
So a few chickens does not seem like much. But when there are 100s of chickens, 30 - 40 goats and several food gardens in a neighborhood it is a more resilient form of scaling. Now you have a decentralized food web and services to support it.
Am telling you what I know works. I am not guessing.
You are speaking to resilience and I agree that communities need to be able to fend for themselves in troubled times. But the back yard economy is not at scale compared even to the local "small" professional farmers who need your money more than you need a small flock.
If everyone in my neighborhood is giving away eggs for next to nothing cuz so many chickens then why on earth would I need a local egg farmer? He may have to farm something else fren. Something harder to farm. Bring more value. We got all the eggs over here already.