It's an example. And hyperboly at that. But you'd be surprised (at least I am) at the patents that are granted that really shouldn't be, but once they are have nearly magical powers given to them by existing laws to resist being overturned. The point was that it's possible to have an extremely stupid patent that really shouldn't have been legal or possible get granted anyway and cause big problems to small guys like this. He's got a great idea but not much money or clout. The patent system will almost certainly do him more harm than good.
It strikes me that many of the folks who defend patent law as it stands now most stridently are largely oblivious to the innovation that is being stifled by it's operation.
It's worthwhile to point out that he's producing this steel through his own venture where the process "is run at his proprietary lab setup at SFP Works, LLC., in Detroit."
Perhaps you and he share the same view of the value of patent protection. Certainly, I'd be concerned about the appropriation of this technology by foreign countries with less respect for US intellectual property protections.
I don't know much about patent law. However, when I search for "cooling metal with water" on Google Patents, I get over 27000 hits. So, the concern is there that maybe someone does.
It strikes me that many of the folks who most stridently object to patent law don't actually know much about it.