On a modern smartphone, the screen consumes more power than the CPU (>3x), so the power advantage of the ARM over Intel chips gets diluted, even taking into account that differences in use between users are huge, rendering power consumption characterization impossible (see Exhausting battery statistics). That ARM chips are so energy efficient it’s a history of unintended consequences and path-dependence: the packaging of the first ARM chips were made in plastic to keep costs as low as possible, instead of using the more common ceramic packaging, as in Intel chips, so they had to keep the power dissipation below a watt. And now, it’s also path-dependence what keeps Intel outside the mobile world: everyone will keep on using ARM chips, even if the power efficiency advantage gets irrelevant.

Will Intel dare to change from being a vertical integrated manufacturer to an open licensor, just to beat ARM, even if that means lower profit margins? Or will they risk seeing their ISA get less executed all over the world?