If you need CUDA for certain applications in example, its better to use Nvidia.
Depends on budget. PyTorch works nicely on ROCm and, for me, bigger constraint is available VRAM than GPU speed and looks like AMD has cheaper RAM, comparing their cheapest 16GB cards AMD is 33% cheaper than Nvidia where I live, and there was some card 45% cheaper few months ago. Huge savings if on limited budget.