Nvidia isn't very big on opensource either. Most CUDA libraries are still closed source. I think this might eventually be their downfall, because people want to know what they are working with. For example with PyTorch, I can profile the library against my use case and then decide to modify the official library to get some bespoke optimization. With CUDA, if I need to do that, I need to start from scratch and guess as to whether the library from the api already has such optimizations.