The big problem right now is that ROCm, AMD's equivalent to Cuda for deep learning, is not supported for the consumer Radeon Navi cards. I had hoped it would be supported in ROCm 3.0 when that was released - but there has been no official word, which is worrying. If AMD are to compete in the GPU/DeepLearning space, it will be because they have hardware that is competitive (not even as good as Nvidia), low cost, and d…
I agree that the lack of (official) Navi support is just bad strategy on AMD's part, but I disagree with your numbers. Their goal needs to be performance parity or dominance, and then perhaps offer a slight discount. That's how they're succeeding with Zen on CPUs. Offering the kind of steep discount you write about is just bad business.
It looks like the 10980XE is the best answer. But in fairness, I believe it and its pricing was exactly an answer to Ryzen 9.