I think post scarcity world will most likely not happen, because as resources become available easily, we compensate for that by increasing our population dramatically. Its not that we do it on purpose, it just how it happens to be for all living beings, from bacteria to trees, and from whales to humans.

Maybe though, there is some hope that in future, the population rise will stop, and we will slowly and steadily move towards a world where no one sleeps hungry.