That's a whole other mess, the 12th and 13th gen P-core design does technically support AVX512 but the smaller E-cores don't, and rather than try to reconcile that mismatch in software they just disabled AVX512 altogether to make the cores all behave the same. If they hadn't decided to implement E-cores then 12th/13th gen would have had AVX512 support.

Some motherboards allowed you to enable AVX512 on those chips if you disabled the E-cores, but then Intel started permanently fusing off AVX512 in hardware on later batches.