The best companies can get up to 90% accuracy. Most are closer to 80%.
But it's important to remember, we're expecting perfection here. But think about this: Have you ever asked someone to book a flight for you? How did it go?
At least in my experience, there's usually a few back and forth emails, and then something is always not quite right or as good as if you did it yourself, but you're ok with that because it saved you time. The one thing that makes it better is if the same person does it for you a couple of times and learned your specific habits and what you care about.
I think the biggest problem in AI accuracy is expecting the AI to be better than a human.