Agreed. However you can also see that Elon doesn't seem to be all too eloquent in his speech or comfortable (at the time anyway), which may account for it. In addition, you can tell that he hasn't necessarily planned out what he's saying here. When he uses "I think" it sounds like it's a thought that he has just then constructed -- as in what he's saying is intuitively correct -- however he seems to realize himself that what he's saying may not be universally true.