Nvidia has had modern ARM chips (the Tegra series among other) for at least a decade now. Any company can license ARM tech.
Just licensing the designs puts a company on a lower chipmaking tier with Qualcomm, Samsung, Apple, Huawei, etc.
NVIDIA Carmel is NVIDIA's own Arm v8.2-A design [0]. They only licence the architecture. The core is quite interesting, as it's doing dynamic recompilation for an underlying VLIW architecture.
However, NVIDIA Orin[1] (followup for Tegra Xavier) will use a Cortex-A78 core[2] (formerly Hercules) licenced from ARM.
[0] https://en.wikipedia.org/wiki/Project_Denver
[1] https://nvidianews.nvidia.com/news/nvidia-introduces-drive-a....
[2] https://en.wikichip.org/wiki/arm_holdings/microarchitectures...