Most climbing helmets these days IMO are really poorly designed for serious impacts and are rather delicate. Check out the shitty coverage most afford the front and sides of the skull. I think they're designed more to be light and comfortable so that people will wear them. It's a catch-22 since if it's a hard shell 5 pound motocross-style helmet, nobody would wear one.
I'm glad this poor guy had something on his head though and hopefully it reduced the impact and extent of his head trauma.