It's not "their" linux support it's linux software support for ARM. A lot of software has x86 SIMD acceleration but doesn't necessarily have ARM SIMD acceleration.
Apple supports Linux via virtualization. If you ask me, that's the most sane way to run Linux on macOS.
You'd have the same ARM performance on Linux questions/problems when run under virtualization though, no? That doesn't actually change the complaint or situation here.
Steve jobs maniacally responds to your email from the grave.