On Mon, Jun 29, 2020 at 7:41 PM Raymond Hettinger <raymond.hettinger@gmail.com> wrote:
Perhaps you don't want to believe the results, but the timings are careful, stable, repeatable, and backed-up by a disassembly that shows the exact cause.  The builds used for the timings were the production macOS builds as distributed on python.org.

This points more to specific builds needing to be fixed, if their build options result in significantly un-optimized code on the same cpu architecture.