There's another thing that CEOs do which is provide values guidance and inspirational leadership for a company. That's not something a robot can do...yet.
That might be what they are supposed to do but apart from my current company, this has happened in precisely none of my previous employers (about 5 of them).
At one company, I didn't even know who the CEO was. We had some company party because we won an award and I had to ask my colleague who the guy was who was speaking. Awkward (but at least I didn't have to ask the CEO who he was).
LOL that happened to me once. I was at some unrelated event and was wearing a company shirt. Someone mentioned to me that her husband worked there. She said his name, and I remarked that I didn't know of him. She sort of stared at me and said with a tone of incredulity, "he's the company vice president!"