I think the challenge here is that when people think about wealth creation they directly associate it with a net productive activity. In theory A & B can satis

I think the challenge here is that when people think about wealth creation they directly associate it with a net productive activity. In theory A & B can satisfy their own needs in the above scheme. Or we could have a village where everyone satisfies exactly one other persons material needs. These activities do not result in net wealth creation. On the other hand if A makes X and X is consumed by B through Z then A has freed up B through Z to do something other than making X. Even then there is an argument to be made that some forms of production are self-limiting in that society as a whole cannot continue to be more productive if everyone is involved in specific kinds of high labor, low scalability activities which do not lend themselves to improvements over time.