What do you mean reliably distinguish a computer from a human? I haven't been surprised one time yet. I always find out eventually when I'm talking to an AI. It's easy usually, they get into loops, forget about conversation context, don't make connections between obvious things and do make connections between less obvious things. Etc.

Of course they can sound very human like, but you know you shouldn't be that naive these days.

Also you should of course not judge based on a few words.