with a Rosetta-style translation

Apple fans before their favorite binary translator came out: qemu-user? Eww… ELBRUS with lintel? Ewwwwww, you suck in past century!

Apple fans after their favorite binary translator came out: We have the Never Seen Before™ technology that was pionered by company we lick.

outside of Apple’s proprietary M/A-series CPUs, there don’t appear to be high-performance ARM CPUs that would fill such a role, though this probably won’t still be the case in a few years.

They exists for many years. There are HPC cores in Cortex-A, entire Cortex-X and super HPC Neoverse cores, but they are rarely seen outside of datacenters.