I could imagine CloudFlare using GPUs for image optimization or video encoding. They do a lot more than caching these days.

Neither is “great” on a GPU:

• Image optimization is still mostly software: JPEG, PNG, WebP. GPUs do not bring much to the table here at all, and consume a lot of power, which is likely to upset the hosting ISP of that cache node.

• Video encoding is better, but still average. NVENC (Nvidia’s encode Engine) has some quality challenges and limitations.

Further, doing this at the edge makes less sense: if you have to fetch the source material from the origin, do the heavy lifting centrally and store the results at the edge. Storing 4-5 renditions is cheap compared to GPU running costs here.

I think the question about caching was separate from the question about GPUs. I don't think it was meant to imply GPUs for caching.