Now that wasn't all that difficult, was it?
Perceptive glimpse of the obvious that there is no contractual claim or legal right to SS.
SWR didn't say that it was a contract.... "a contract if you like"... suggesting that it is similar to a contract.
I have friends and relatives who believe they do have a contractual or legal claim to SS, and I see claims to such often on the net. Some of those people grok[1] SCOTUS (Supreme Court Of The United States) rulings, some don't, but it's what I point to first, then try to explain in simpler terms if someone like yourself says "what!?"
[1] Read "Stranger in a Strange Land" by Robert A. Heinlein for a definition.