Fun facts: (AKA explain the joke, making it less funny to some, but more funny to me)
Special K is also slang for ketamine, a drug popular with some high profile oligarchs and other elites.
So the "K" in K-shaped economy (wealth divergence) and the "K" in Special K (ketamine) land on the same social group *the ultra-wealthy on the top arm of the K * making the letter a convenient pun for commentary on inequality and privilege.