CrossFit has an unusual increased risk of a disorder both deadly and detrimental to fitness

The article presented no data other than some evidence about meme propagation in the Crossfit community.

Rhabdo is a consequence of severely overexerting your muscles and is not specific to the types of exercise that Crossfit does. It is specific to motivation and the claim is that, basically, Crossfit overmotivates the newbies. Well, maybe. And maybe other fitness programs do, too. Without data it's really hard to tell and so far I haven't seen any.