Being able to communicate in human natural language is a human characteristic. It doesn't mean it has all the characteristics of a human but certainly one of them. That's the convenience that you perceive--Because people are used to interacting with people and it's convenient to interact with something which behaves like a person. The fact that we can refer to AI chatbots as "assistants" is by itself showing it's usefulness as an approximation to a human. I don't think this argument is controversial.