Give a man a fish and he eats for a day. Teach a man to fish and he stops voting for the Free Fish party.
The article even says that "collapse theories are considered fringe" and presents two other pieces of work that use the exact same methodology with much much less drastic conclusions.
It's right in the OP.
Also, I believe that very few would actually die. Survival instinct is a very strong motivator. After a few do die from their laziness, the rest will get the message and we will see them start taking jobs that they have scorned because it is easier and more comfortable to live off the rest of us.
Finally, it is morally reprehensible to enslave others. By saying that non-producers have the "right" to what the producers make and earn is making those producers slaves. When you punish achievement and reward laziness and non-achievement, nothing good at all can come of it. It is not sociopathic to place the wellbeing of the majority ahead of the wellbeing of the few, especially when the few are quite often in their predicament due to their own choices and their own laziness. The needs of the many outweigh the needs of the few.
Be sure to work hard and get lots of overtime. People on welfare want more steaks and free upgrades to smart phones with unlimited data packages.