re: Why does "How I met.." get love, but "The Big Bang..." gets hate?

The issue with BBT is that the characters are static. Sheldon is a genius savant, who displays obvious characteristics of Asberger's syndrome. Chuck Lorre wouldn't actually expose Sheldon's social issues in an episode, because Middle America would feel terrible about laughing at an autistic person. People who suffer from Autism and Asberger's are well aware of their struggles to adapt to social conventions. We are led to believe that Sheldon is one of the smartest people in the world, but somehow doesn't understand his social awkwardness. Oh it's just funny, because smart people don't talk normal with us regular folk. It's not like smart people have normal conversations with people of their intellect or, shudder, with less intelligent people.

Abed on Community is actively autistic. He knows it. His friends know it. The audience knows it. His character can develop because we're all aware of his quirks.

The rest of the characters have different ways of expressing the obsessions with sex. Raj displays sexually ambiguous attributes, despite being a obsessed with heterosexual sex. Walowitz is a sexual pervert, who somehow gets married without actually developing past his obsession with sex. Leonard is supposed to be the normal guy who wants a relationship, but also likes sex. Yet, he just comes off as completely uninteresting.