It is important in the sense that many Linux programs did not bother to support both the Intel video API and the NVIDIA video API, so they work only with the Intel video API, which is also supported by AMD GPUs.

Programs that are converted to Vulkan should work with any GPUs.

VA-API works very well with the GPUs that support it, while the NVIDIA video API also works very well with the GPUs that support it, i.e. the NVIDIA GPUs.

The Vulkan video API has worked well for some time on NVIDIA, I switched my video player to it long ago.

Eventually the Vulkan video API should work well on all GPUs, so there will be a unified video API on Linux.