In addition to the underlying architectures to implement them.
It's not inconceivable that Intel simply made enough arch / process / design mistakes that they've ended up at the end of a performance box canyon.
It's happened before. Pentium 4 was a deadend, while Pentium M-derived architectures continued to improve performance.
So "Apple realizing continued gains by optimizing a less mature architecture" is one hypothesis.
But "Apple realizing continued gains by optimizing a more evolveable architecture" is a valid alternative.
In addition to the underlying architectures to implement them.
It's not inconceivable that Intel simply made enough arch / process / design mistakes that they've ended up at the end of a performance box canyon.
It's happened before. Pentium 4 was a deadend, while Pentium M-derived architectures continued to improve performance.
So "Apple realizing continued gains by optimizing a less mature architecture" is one hypothesis.
But "Apple realizing continued gains by optimizing a more evolveable architecture" is a valid alternative.