As someone with an Autistic sibling, that’s almost certainly why you struggle to understand it. The lack of clarity and precision that you perceive in “natural” dialogue is the more significant and complex dimension of social interactions that is what’s not being said, the implications and assumptions that lie behind silence or glibness, and the inability to grasp those unspoken social meanings is a direct marker of autism.
The purpose of “natural” dialogue is not to be unclear or imprecise about its content - it’s to convey the character of the person speaking.
