No, the argument was the rest of the post that was cut nastily... and even the quoted part is summarised badly: I say that crash helmets might work if you crash, not that they definitely will!
But of course it would be far better if cyclists crashed even less... and of course we can achieve that, such as by improving road design through sustainable safety or Vision Zero or similar and not putting obvious crash hazards in the way of cyclists. It may even be that cyclists would crash less if fewer wore crash helmets, but that needs further investigation.
The bigger problem with crash helmets is they're dealing with a small fraction of an already-unlikely event... truly obsessing about what to do about one toenail of the elephant in the room... which is that lots of people won't ride no matter how much safety gear you try to persuade them to wear, because they don't have good streets to ride on, they don't know the routes (which are often ill-signed) or they don't know how fast and practical it can be. Crash helmets don't make the streets nicer, don't help you to find the routes and even make cycling slower and less practical faffing about with special hats.