Stupid changes - Zhonya's Hourglass

Why does this now cost 500 gold more and have 20 less AP? One of these nerfs would have been stupid but adding both together? What is the point of this change? It isn't like it was used on every single champion. It has a specific use for AP champions who now have even less to work with while paying more. I'm really stunned by the amount of stupid changes so far but this one makes even less sense than the rest I've seen.