Well, the power efficiency about Apple Silicon combined with their firmware and drivers is really something. ARM doesn't have much to do with it.

Well, I hate to be the bearer of bad news, but Apple Silicon CPUs are entirely based on ARM architecture, and they elected to use ARM architecture, among other reasons, because it has lower power consumption and lower heat generation compared to CISC architectures.

This is just fokelore.

“ARM architecture” in the sense it’s used by Apple is just an ISA. The ISA obviously has some effect on power consumption (e.g. avoiding complex CISC decode). But in reality, by far the most significant driver of CPU efficiency and power consumption is process node.