I would love to see an example of reasonable code not seeing any benefit. On first generation SKX, we saw 1.5x speedups vs AVX2, and that was IIRC even without

I would love to see an example of reasonable code not seeing any benefit. On first generation SKX, we saw 1.5x speedups vs AVX2, and that was IIRC even without taking much advantage of AVX3-only instructions.