It depends on the product/service, but if it mostly works and there is a reliable way the agent can escalate to a real human if necessary, I can see potential in many areas. Most support requests did not try out the standard solutions or read any FAQ. So real humans aren't bored to death giving the same answers hundred times a day, but can focus on the real support cases requiring human intervention.

I did actually experience some chat bots that were helpful without needing a human to get my answer quick and some gave a number to call after exhausting their scope. But I am aware, that this is not standard.