Here is a CPU from 2020 that does not support AVX nor AVX2 https://www.intel.com/content/www/us/en/products/sku/199288/... very low budget and probably not common but this is why one might choose not to require AVX2
There's a related discussion on hn from 2020 about lack of AVX here https://news.ycombinator.com/item?id=24577069