Yep they do this for all their platforms, set a battery target based on ~90%tile daily usage of particular form factor (e.g. 18hr watch/iphone, 10-12hr macbook/ipad) and then let ID & chip teams do whatever they want to hit that. The value add of every additional minute/hour of battery life drops off from there because daily loops for charging are realistically what everyone will do, and there's more value add in other places like making things thinner, faster, or do something new.
