https://developer.nvidia.com/nvidia-video-codec-sdk
They offer a hardware decoder completely free of charge.
Why don't we have this in Vegas 16?
a new version of Movavi will be released this autumn .
The producers promise it support Nvdec. Here is the translation of the technical support response:

-"Unfortunately, the hardware NVDEC decoder is not implemented in the current version of the editor.
Support for this decoder will only be added in the next version of the editor (15).
The release of the new version of the editor will be approximately in mid-late September, the exact date yet, unfortunately, no.

I want to know why we can't use our Nvidia video converters at full capacity."
Why low encoding load and no decoding?