> In comparison, I think Arm is actually a very strong cautionary tale that focusing on power will not get you to performance.

Hugely underappreciated. Someone involved fully understood that "you don't get to the moon by climbing progressively taller trees".

The other two times Arm had great performance were the StrongArm, when it was implemented by DEC people off the Alpha project, and the initial ones, which were quite esoteric and unusually suited to the situation of the late 80s.