darwin/arm64 does not support CPUID or HWCAP CPU feature detection like other operating systems on arm64 currently supported by Go.

A new way using sysctlbyname will need to be implemented to detect if for example hw.optional.armv8_1_atomics is set to 1.

https://developer.apple.com/documentation/apple_silicon/addressing_architectural_differences_in_your_macos_code

If someone has an M1 Apple Silicon Mac please post the output of:
sysctl -a | grep "hw\.optional"