What is the support of AVX-512 in MacBookAir9,1 This could be checked if you have the new 2020 MacBook Air by using command:

sysctl -a | grep cpu


I am not in possession of this Mac and can not find this documented by Apple or elsewhere online.
According to this Anandtech article and ark.intel.com site it looks like they have it:

Core i3-1000ng4

Core i5-1030ng7

Core i7-1060ng7