I don't want to overstate it; I've written a lot of SIMD in my life too. If you've got audio processing that needs to run in a realtime thread, I can see how SIMD is appealing, because we don't really have mechanisms to achieve realtime on GPU (yet). However, for a lot of seriously heavy computation, it seems like doing it on the GPU is a win. For the cases where memory transfer back and forth to the GPU is expensive, even integrated GPU should offer significantly more computational resources than even AVX-512.

One of the use cases I'm thinking of is font rendering, where I published a SIMD-heavy prototype a couple years ago, and it's blown out of the water by a newer GPU-based approach: http://pcwalton.github.io/blog/2017/02/14/pathfinder/