People are really hyped for this game (they love Avatar + Platinum. It's a dream come true). First preview is out, people are really happy it sounds good. Jason bluntly says: it's a Sony preview, do you REALLY think they wouldn't make it sound good. Then after that other sites start releasing previews and they are also positive.
So following that timeline, I can see why some would think Jason was just kind of trying to be a buzzkill.
Just my 2 cents. I don't mean to offend anyone. Trust me, I'm a huge avatar fan (obviously). I love Platinum. And yes, the Sony preview got me excited. But I see nothing wrong with Jason being skeptical of a Sony preview (or previews in general). Whatever.