[swang720]

They weren't weighed down by the legacy bloat in the x86 instruction set architecture.

[dboreham]

Except we already had 30 years of other ISAs without that bloat, and they were all resoundingly beaten by Intel.

[wahern]

I think the answer is that the marginal benefits of a better ISA were less than the marginal benefits of better node process and faster iteration that Intel enjoyed. But for various reasons Intel no longer enjoys those advantages. With TSMC Apple has the process advantage, and their smartphone business has given them both the motivation and cash to iterate their architecture faster than Intel. The simpler ISA has compounded those advantages.