Respectfully disagree with this concept.
My chickens are *technically* free-range bc they freely go in/out of coop into a large and varied run. However, I don’t refer to them as free range bc I’m not letting them into pasture or forest or lawn where they would be foraging for a time.
A person may fence in an acre or more for their chickens, and according to your statement, they would not be free range. But, the chickens are free ranging in a large and varied natural area…I say they are “free ranged”
My chickens get to free range some times. I open the run gates and they go here and there, scratching, picking, running, eating various greens. But, it’s limited. More often, I’m tossing garden greens or grass or flowers to them during active garden season (otherwise the chickens destroy the smaller garden plants).
Fences do not take away the free range aspect of chicken keeping. Often it is a smart way to manage things.