There would be a decent amount of human misery in the short term if we changed the incentives (and not just for the people learning that other people don't owe them a living; the way they act out will impact peaceful and productive citizens also), but nothing on the scale that comes from creating multiple generations of people that do nothing but collect checks and occasionally engaging in crime ranging from minor to major.
I think you are greatly underrepresenting the catastrophe that would ensue in this arrangement, as well as the “simplicity” of just striking 60 year old incentive programs off the books across the entire country.
The instantaneous effects of doing something like this would resemble a legit genocide in the US.
If you think one city block in Seattle being briefly taken over by the citizenry was bad….think about the total shitshow that would happen just in Jackson. The police would completely disappear. Jails would be taken over and all criminals released. Anyone who actually was “productive” would be forced to leave their homes / belongings, elderly relatives, etc, and GTFO as fast as possible. It’d be a nationwide nightmare. Nationwide. Not just Jackson. Because what you’re talking about eliminating are federal programs.
And the ultimate problem - even if all those people in Jackson that lost their assistance actually wanted to be productive, there is no vessel for them to actually BE productive. There are no jobs available for those people to work. And the last thing that the private sector is going to do is start bringing their business opportunities to a Mad Max universe that would unfold from what you’re talking about.
There’s just no way to put the toothpaste back in the tube. A monster was created, and now that monster must be continually fed to keep it from destroying everything around it. That’s the unfortunate reality.