To be fair, it seems a lot of these images come from the same 2-3 sources. They just pollute the internet with their slop. I believe they have many other slop images for everything so blocking them would probably cut a lot of these results. They might not want to completely remove these sources because they actually have useful images as well but at this point DDG should just cut them out because they're heavily infected.
If this goes on, we probably end up with a curated human-centric small and limited internet at some point and it will be hard to protect it. That probably also means far from ads and SEO-based internet too, since that's what started the pollution in the first place.