I’ve never met anyone who uses them, but I’m also not sure people actually think it’s sentient. I’m sure some do, but I’d assume the vast majority are just looking to have a conversation, and they don’t care if it’s with a person or a (pretty good) chat bot.
Also, there is a way to use it ethically. As the post mentions, run it locally and know what you’re doing with it. I don’t see any issues if you’re aware of what it is, just as I don’t see any issue using auto-correct or any other technology. We don’t need to go full Butlerian (yet).