Allow me to modify the bit you quoted, then. I usually try to be more careful, and I apologize:
...If he would at least qualify his criticism of private space industry's probability of establishing a Mars colony...
Why do we decry the ability of the private sector to do stuff in space? I'm not saying "they absolutely will establish a Mars base!", I'm taking issue with anyone saying outright that it can't be done. It's a silly statement, regardless of whether it's made by a well-respected Doctor of Philosophy in Astrophysics, or someone who is somewhat less qualified.
Don't get me wrong, I like the guy, and he's curt and painfully correct on many far more controversial topics. I just think that on this statement, there is room for disagreement.