I think that people compare cats to dogs as both are common pets. Dogs are very expressive, while with cats you have to pay attention and spend some effort to learn their behavior and habits. Many people don't have time or interest for that.
the whole "cats are assholes" thing comes mostly from people viewing cats through a dog lens, expecting them to act like dogs, then being shocked they don't thus they most be aloof and/or assholes
I'm so tired of it. I wish people learnt to communicate with cats in cat!