CUDA is a GPGPU software layer that is very mature, and integrates with C,C++, Python, Fortran very well. AMD just never really got the same quality of GPGPU software in the last 20 years. 99% of scientific computing that uses GPUs (which is a lot since they are so much faster than CPUs for linear algebra) have gone to Nvidia because of this. All of the big AI libraries (Tensor Flow, PyTorch) basically ended up writing around CUDA, so they just didn't write things for AMD. Plus if you go and look at a job for signal processing or whatever at say Lockheed Martin or Raytheon, they specific CUDA.