What happens to the people displaced, I dunno. Malthusians and Luddites have been telling us we're all going to die in a mass of unemployment and poverty for a quarter of a millenium, and they've been consistently wrong, mostly because they lack the imagination (as we all do) to see how humans will cleverly adapt to the new reality.
In the medium term, agricultural robots may displace a lot of pesticide use as well, because if you have a solar-powered 24/7 robot weeding, you don't need chemicals. This also should be viewed as a good thing.
But a world where robots can do everything, including writing this post for me, creates an interesting problem. Most people--especially men--are not well-suited to not having work. How we fulfill people's need to work in a world where there is no work that needs to be done is an interesting problem to have. But remember that there was a Roman emperor who killed off an early attempt at industrialization and rudimentary assembly lines because he feared what the newly-unemployed would do, and worried that surplus slaves would revolt. It's hard to argue, knowing what we know now, that he made the right decision. Our inability to see our own future shouldn't stop us from embracing it.