To add to this - even if the motherboard manufacturer allows this despite Intel's advice, in their stock configuration none of those CPUs allow AVX-512 instruct

To add to this - even if the motherboard manufacturer allows this despite Intel's advice, in their stock configuration none of those CPUs allow AVX-512 instructions out of the box. You need to knowingly and conciously go into the BIOS and disable all efficiency cores first, to make this option even appear. So "as sold" the product doesn't support AVX-512 instructions and the advertising is absolutely correct. Just like you can overclock the CPU but it doesn't come overclocked out of the box(and Intel assumes no liability if you do overclock it).