The fact that a souped up autocomplete system can solve basic algebra is already impressive IMO. But somehow people think it works like SkyNet and keep asking it to solve their calculus homework.
Looking for emergent intelligence. They're not designed to do maths, but if they become able to reason mathematically as a result of the process of becoming able to converse with a human, then that's a sign that it's developing more than just imitation abilities.
Because it's something completely new that they don't fully understand yet. Computers have been good at math since always, everything else was built up on that. People are used to that.
Now all of a sudden, the infinitely precise and accurate calculating machine is just pulling answers out of its ass and presenting them as fact. That's not easy to grasp.