While I agree that the banned Bonus buys doesn't serve its purpose, I don't know about the numbers of cashout. Best guess would be that that haven't changed much. Like I don't think there was a spike in cashouts after Bonus buy games came to the slot world.
With bonus buys you might just have lost the money a lot quicker since it is more volatile than regular play
What I do know is though that if slotting begins to be boring, you, me everyone should always stay away instead