That scenario doesn't seem terrifying to me, though it's pretty vague. He says there are job losses and revolution is impossible but so what? Realistically in this scenario people just vote to raise taxes on capital owners and give themselves a paycheck. Machine labor is apparently extremely capable and near-free in this scenario so owning even a small amount of capital makes you effectively rich in absolute but not relative terms. I guess he's assuming democracy breaks in a way that is pro-capital owners somewhere along the way but that isn't actually stated.