The whole point being made in the video (which I think very few here actually watched) is that the only ones who benefit from this contracting/expanding are the top 1% (realistically more like 0.1%).

If the economy is growing (not a zero sum game as you say), but the economic ability to own assets is decreasing then you are creating a situation where after some time all assets are owned by only very few. I'm not sure if you consider that a good basis for society. I certainly would prefer my children not to live in a cyberpunk distopia.