The whole article is based on the assumption that once basic necessities are covered, huge numbers of people are going to call it a day and cease economically profitable activity.
I think the opposite will happen: once people have the basics taken care of they will become more economically active. They will take risks they couldn't before because of the overhanging risk of complete destitution. They will negotiate for better wages because everyone will know they have a perfectly viable alternative. They will invest time in themselves because they won't have to worry about how they will live if they don't have a job while they study or launch a business.
Further, there will be more money sloshing around and creating broad-based demand for goods and services that these self-same people can try to capture through their own industriousness.
I strongly believe that we have as many on welfare right now because we have a huge sector of our population that have the following choice: live in poverty on welfare with lots of free time or live in poverty while working your ass off treading water. And the reason they remain in poverty is that their employers know that there isn't a great alternative for those marginal employees so they pay just enough to keep their employees afloat but not enough that they can get ahead. UBI or negative income tax (my personal preference) would deeply change this calculus. People could spend their time and energy to truly better their situation rather than merely not lose everything.
We're not going to turn into a banana republic where only the economically elite and the political class keep each other happy and everyone else are kept just happy enough to avoid revolution. There isn't a lot of democratizing of economic power in those regimes.