I understand this is important mainly for Nvidia GPUs. Is there any benefit at all for this (vs the existing VA-API) on Intel and AMD graphics? VA-API seems to work very well on both of these platforms, as far as I've tested.
VA API has some caveats and also requires one to disable sandboxing of the media process.
Sorry my comment was related to the nvidia vaapi driver
Considering Intel has vulkan video disabled in Mesa for recent chips, I’m guessing very little.
https://www.phoronix.com/news/Intel-Vulkan-Video-Disable-New