Will technology put some, even many, folks out of a job? Sure of course, that's been happening for hundreds of years. Think of the blacksmiths of the 19th century who drank themselves to death.
And even at the end of it all, people still love the novelty of a human doing something. People still prefer "hand scooped" ice cream enough that it's on billboards.
This is a circular argument though, you say people prefer people and therefore we will have a lot of people around.
Today leaders and rich people requires humans to wage war and to produce goods, those are the main thing creating stability today. When those are removed we are likely to see a sharp decline in number of humans around. Companies cutting out humans and just using machines as leaders and decision makers outcompete humans in peace time, and robot lead armies outcompete humans in war times, and soon human companies or countries no longer exists.
20 years? Is that's meant to be an impressive timescale when we are talking about global economy?
People had talked about building a machine that could play chess at least since they had and had a mechanical turk hoax in 1770. Just because it took a while, does not mean the idea is wrong.