There is an absolutely enormous market for AMD GPUs for this, but they seem to be completely stuck on how to build a developer ecosystem.
Why aren't AMD throwing as many developers as possible submitting PRs for the open source LLM effort adding ROCm support, for example?
It would give AMD real world insights to the problems with their drivers and SDKs as well, which are incredibly numerous.
People would be willing to overlook a huge amount of jank for cheap(er) cards with large VRAM configurations. I don't think they when need to be particularly fast, just have the VRAM needed, which I'm sure AMD could put specialist cards together for.