The cores are limited to the least common denominator, at least in Alder Lake.Or theory #4: Intel want to keep kernel developers on their toes!
Nevermind the scheduler changes Zen and the NUMA layout, moving and scheduling across totally different cores is going to be way harder.
Yes, ARM's Big.little had pioneered a lot of this but didn't ARM always maintain the same ISA and instruction sets between the cores used for Big.little?
While unsupported instruction could cause and exception and either be emulated or forced into the other type of core, this sounds like a lot more work.
Plus, whatever happened to AVX512 taking over the world?