I think VAAPI is still how the gpu is accessed but you can use the intel libva driver (vaapi) or the intel media driver (QSV) (arch wiki page). If I'm interpreting this all correctly.
Some of the recommendations I have seen are Baikal and Radicale. I don’t think either have an official Docker image, but there are a few community-maintained images.
I thought macvlans were only available to rootful Podman?