Yeah, I never got the impression from the Fate Core episode of Tabletop that Wil Wheaton wasn't having fun playing the game. He seemed to be enjoying the fact that he was actually rolling well for the first time in his life and doing the sorts of things that his character concept was designed to do. He was also happy that his fellow players were doing cool things. You also seemed to enjoy creating game details when asked by the GM.
I suspect that the negative reading that Wil Wheaton is frustrated by Fate may be projected on to him by someone who is decidedly biased against Fate and has repeatedly made a lot of bold claims in the past against Fate. Maybe just maybe that colors their perception of the game. Like Wil Wheaton
here positively describes his experience with Fate and this episode. He could by hyping his own content, but I also don't see sufficient reason to doubt his words.