Genie+ exists for 1 reason...MONEY.Yeah, but were you one of the people utilizing one of those online calculators to figure out the exact moment you had to wake up early in order to book them all in advance? If you were, and you knew what you were doing, you had no problems with FP+.
If you showed up to book reservations a few days after the availability opened, would it have been so easy to book the most in demand rides?
Disney has the data and Disney decided the same thing. That's why Genie+ exists.