That is an interesting angle to look at it from. If they're gonna keep pushing this they end up with a strong incentive to make the iPhone even more energy efficient, since users have come to expect good/always improving battery life.
At the end of the day, AI workloads in the cloud will always be a lot more compute effective however, meaning lowered combined footprint. However, in the server based model, there is more incentive to pre-compute (waste inference) things to make them appear snappy on device. Analogous would be all that energy spent doing video encoding for YouTube videos that never get watched. Although, it's "idle" resources for budgeting purposes.
At the end of the day, AI workloads in the cloud will always be a lot more compute effective however, meaning lowered combined footprint. However, in the server based model, there is more incentive to pre-compute (waste inference) things to make them appear snappy on device. Analogous would be all that energy spent doing video encoding for YouTube videos that never get watched. Although, it's "idle" resources for budgeting purposes.