in your link it says you have to explicitly include a gpu option.
it also says in your link that gpu acceleration is still shit quality-to-bitrate:
>Hardware encoders typically generate output of significantly lower quality than good software encoders like x264, but are generally faster and do not use much CPU resource. (That is, they require a higher bitrate to make output with the same perceptual quality, or they make output with a lower perceptual quality at the same bitrate.)
there's a reason it's disabled by default, retard. you should never use gpu-accelerated encoding unless you're a streamer using obs with a cpu too weak to handle it