@nprofile1q... Is that unedited footage directly from your recording software?
Either way, I promise you it can be compressed further an not look like trash. Also, "High Efficiency" doesn't mean low bitrate; it means less loss (in comparison to 264).
Do you have ffmpeg, and also know how to use it? You can compress it with your hardware encoder so it's fast to complete, and lossy compression it especially good quality with HEVC.