Nice you found out and mention it here.
It has been like that since new generation x86 CPUs provide compatibility with the previous generation with more speed... Pushing an uncalculable number of tons of perfectly working hardware to the trash, most of the time to keep executing the same tasks with an updated software.
When the software performance/optimization declines, the hardware is accused of being too old. Even if hardware speed never declines with age. I understand we need new hardware for new usage; but not for a new version of Windows, Office or MacOS.
Just check https://en.wikipedia.org/wiki/Andy_and_Bill%27s_law
It goes the same with webpages load, library number and sizes... always a declining optimization with faster hardware.