Comment by veunes

The problem is that "hardware-agnostic PyTorch" is a myth, much like Java's "write once, run anywhere". At the high level (API), the code looks the same, but as soon as you start optimizing for performance, you inevitably drop down to CUDA. As long as researchers are writing their new algorithms in CUDA because it's the de facto language of science, Google will forever be playing catch-up, having to port these algorithms to XLA. An ecosystem is, after all, people and their habits, not just libraries.