Comment 7 for bug 1708102

Re hwdec:
https://git.srsfckn.biz/mpv/commit/?id=dbef5b737e2f994f02923c8214cba368b663a655

Also, off the top of my head:
- vaapi-egl does not work on AMD hardware AFAIK, breaking hwdec on Wayland and resulting in low-quality or incorrect color conversion when vaapi-glx is used
- VDPAU does not support 10-bit video (and 8-bit HEVC is buggy with NVIDIA drivers), is generally broken with FOSS drivers
- CUDA decoding is just broken in general
- there’s this gem https://github.com/mpv-player/mpv/issues/4383
- video filtering does not work with non-copy hwdec

Also, at least in my testing, I’ve noticed no energy savings when using hwdec, on both desktop (measuring at the wall) and my laptops (according to PowerTOP). Nobody ever bothered to extend the comments in the default config after all those issues that were encountered. Perhaps I should do that.

If you *really* want to enable hwdec despite all that, at least restrict it to the “safer” -copy modes by using auto-copy.

Re Wayland:
- video-sync=display-resample is unavailable with the Wayland backend, which also breaks interpolation (a very popular feature to reduce judder)
- Wayland support in mpv is not mature by any stretch, plus we have less than one person available to work on it regularly