In no way am I remotely suggesting "all", the mobile web has a long way to go, let alone the .mobi extension.
I think he is referring to "corporate" end users buying generics for development not corporations developing .mobis for their already existing websites. At least I think that it is his arguement although I don't see that it holds much merit.
You don't really see "corporate" end users going after generics in the .com even. Heck, look at pizza.com, none of the major pizza chains has gone after it until this point and even this recent sale could have been to another domainer. Pretty much all the major sites out there are brandables that were probably purchased for reg fee.