Worth it, but not free
Have you ever seen the silly meme saying something like: "If we all gardened and traded our surplus with each other, we could eat for free!"?
When I see that I wonder what the person's definition of "free" is.
I think of "free" as meaning "without cost"; something for nothing.
Even when I pick Rocket Mustard, purslane, or prickly pear out of the yard to eat, there is a cost. It takes labor. Both for harvesting and for preparing.
Anyone who thinks only in terms of money traded for the food is missing almost everything related to cost.
This doesn't mean I am opposed to growing your own and trading the surplus. I'm not. I think it's a great thing to do and I encourage everyone to try it. But let's not fool ourselves that the food produced is in any way "free".