I think that may be your own interpretation of the show depicting a few flaws.
I have only watched a few episodes (something about the show irritates me intensely), but I had the impression that Penny was your stock normal character / foil / straight (wo)man and indeed a bit out of Leonard's league. Browsing the Wikipedia and BBT entries for Penny, they give me the same impression - a basically good normal character who in several respects is superior to 'the boys'. And certainly not an all-around 'despicable, pathetic person'.
You obviously didn't get to the part where she spoke of her past as a bully in high school (and I mean the seriously violent kind of bully, not just the steal your lunch money and make fun of you kind) and where she stole clothes from one of those donation containers.
Or the part where she chides Leonard for selflessly and spontaneously helping her with college, alleging that she wants to be her own person and win on her own merit,; she gets a B minus for her work... only it turns out she had Amy and Bernadette do that for her.
In the same episode, she jus...
This is my first attempt at starting a casual conversation on LW where people don't have to worry about winning or losing points, and can just relax and have social fun together.
So, Big Bang Theory. That series got me wondering. It seems to be about "geeks", and not the basement-dwelling variety either; they're highly successful and accomplished professionals, each in their own field. One of them has been an astronaut, even. And yet, everything they ever accomplish amounts to absolutely nothing in terms of social recognition or even in terms of personal happiness. And the thing is, it doesn't even get better for their "normal" counterparts, who are just as miserable and petty.
Consider, then; how would being rationalists would affect the characters on this show? The writing of the show relies a lot on laughing at people rather than with them; would rationalist characters subvert that? And how would that rationalist outlook express itself given their personalities? (After all, notice how amazingly different from each other Yudkowsky, Hanson, and Alicorn are, just to name a few; they emphasize rather different things, and take different approaches to both truth-testing and problem-solving).
Note: this discussion does not need to be about rationalism. It can be a casual, normal discussion about the series. Relax and enjoy yourselves.
But the reason I brought up that series is that its characters are excellent examples of high intelligence hampered by immense irrationality. The apex of this is represented by Dr. Sheldon Cooper, who is, essentially, a complete fundamentalist over every single thing in his life; he applies this attitude to everything, right down to people's favorite flavor of pudding: Raj is "axiomatically wrong" to prefer tapioca, because the best pudding is chocolate. Period. This attitude makes him a far, far worse scientist than he thinks, as he refuses to even consider any criticism of his methods or results.