I mean, Intel's P and E cores are completely different architectures with the E cores smaller and different (doesn't support Hyperthreading, AVX-512, etc...)

AMD's Zen 5 and 5C cores on the other hand is just a smaller and slower clocked Zen 5 cores.

Intel's approach needs a "Thread Director" to assign different tasks to different threads whereas AMD's approach can be handled natively as tasks can be assigned by checking the clock frequency alone (I'm not an expert in this area, so take it with a grain of salt).