Google calendar is used for managing your personal life. For example, "Lunch with Bob at 2:00 PM" is a personal event that you will like to be reminded off. You will not want to create such an event on Appointy. Rather you would want it to block that time on Appointy so no one can schedule 2:00 PM. Isn't it?
Appointy does exactly the same. It will block that time on Appointy and creates a gap between your personal and professional life more professionally.