Dude, you are a user just being jealous of the iPad mini 3. iPad mini 3 did only add the touch ID, but Apple made the performance better to convince users but it, they slowed down the mini 1 and mini 2 to make people think about getting the mini 3 or air 2
This is false. How is iOS 8 going to maintain the same performance on devices that are underpowered (Mini 1). The iPad Mini 2 also has not been slowed, it runs iOS 8 the same as the Mini 3. You can't say Apple is purposely slowing device to make them buy new ones, by using an early iOS 9 beta as your example.
The iPad Mini 2 and 3 are identical except for the Touch ID sensor.