Apple stopped using them when Pentium M / Centrino came along because Motorola had no plans to make anything that fast and IBM had no plans to make anything tha

Apple stopped using them when Pentium M / Centrino came along because Motorola had no plans to make anything that fast and IBM had no plans to make anything that low power, and PA-SEMI was five years too late and by that time Apple wanted them to design ARM chips. POWER also has a code size problem -- it's just much larger than x86 and Aarch64 (very similar) or Thumb 2 and RISC-V (also very similar and significantly smaller than the proceeding two). A couple of decades ago no one thought that was a big problem but now it is, not only because you need a bigger more power-hungry L1 cache, but also instruction fetch bandwidth from L1 is now one of the biggest energy users in a CPU core.