American television basically consists of medical dramas, procedural/cop dramas, sitcoms, and a few random things that don’t fall under either of those categories. Even then, the sitcoms are stale, usually involving the same type of characters and plots. With those, you’ll have a “dumb” character, a sexy/”slutty” female character. If the protagonist is a woman, she’ll be a twenty-something trying to find her place in the world and trying to find a man to “complete” her. Otherwise, she’ll be an empty shell with no worth. If the character is male, then he’ll be a skirt chaser who only wants to get laid and hang out with his friends until he’s finally “tied down” by a love interest and “grows up”.
Regardless of gender, both characters will be white. Mindy Kaling is the exception that proves the rule.
Then of course, there’s the “token” character. This is a non-white character who doesn’t really do anything and pretty much just exists so that the cast isn’t entirely white. Sometimes, he/she will fill the “dumb” character role. If the character is African-American, they’ll be “hood”. If the character is Indian or South Asian, they’ll be the butt of jokes involving tech support or call centers or derogatory stereotypes about South Asia.
Basically, this is one of the reasons why shows like The Walking Dead and Game of Thrones are so successful. They don’t follow the same bullshit as the rest of American TV.