Well, this is well outside of my area of expertise, but the only factual dispute attached to the image in wikipedia is that SSI is only available to people essentially assumed to be out of the work pool. From the SSI site: "Little or no income, and Little or no resources, and A disability, blindness, or are age 65 or older." That's a pretty tiny slice of that graph. Maybe it just hasn't been thoroughly interrogated but my gut says that whoever attached that SSI criticism would have probably addressed more severe discrepancies first.
The source-- a libertarian blog-- implies that the problem is welfare itself, but I think the bigger problem is a naive approach to means testing that is entirely divorced from economic reality.
The primary source is a welfare bureaucrat, Gary Alexander, Pennsylvania’s Secretary of Public Welfare, not a libertarian blog: https://youtu.be/Ruzo8bm96Io?t=2191
You mean former Secretary of Public Welfare, who resigned after two years on the job in 2013. He now runs an anti-welfare consulting business. He was highly controversial during the two years he was in the job, and the Obama administration had to step in. He also claimed he was moving to Pennsylvania, and then used public funds to commute to his Rhode Island home instead.
This fact alone doesn't mean much. He was appointed by a Republican governor and could very easily be a liberterian ideologue to the same degree of said blog.
The source-- a libertarian blog-- implies that the problem is welfare itself, but I think the bigger problem is a naive approach to means testing that is entirely divorced from economic reality.