Isn't CUDA/nvidia the go to solution for most local models, with the rest being second class citizents?

Depends. ROCm is pretty well-supported for example.

Non-NVIDIA backends tend to get less support and new features land slower, or features that are expected to improve performance wind up hurting it instead. That sort of thing.

For basic “token in/token out” workloads without fine tuning, it’s probably fine ??