Well the whole Apple slowing older device debate has been beaten to death and Apple claims it was a safety net for older devices of which their batteries would be unable to provide enough stable power. Therefore they had to slow the device down to allow to battery to keep up with the device and increase the longevity of the device even if it meant the device was being power managed under particular workloads.

Whilst we can have our opinions of the legitimacy of this, I am inclined to agree with it. There have been many people on the other side of the coin who have claimed their device instability was fixed after these updates.