Per-core performance has been stagnant in the past decade. Apple already appears to beat Intel's Y-series processors in most things. Scaling the un-core parts u

Per-core performance has been stagnant in the past decade. Apple already appears to beat Intel's Y-series processors in most things. Scaling the un-core parts up to compete on desktop will take some doing, but scaling up into the relatively restricted 15-28W range is much easier. Most importantly, Intel charges a premium for ultra-low power chips. If Apple can make a chip that's 80% of the performance for a couple hundred less per unit, it's a great deal. Moving everything to a unified ISA reduces design and developer costs and increases total control (aka vendor lock-in) which also increases profits.