Yeah, Emby is definitely more focused on video and audio is just sort of along for the ride. The issue itself is with ffprobe but after reason some bug reports it doesn't seem like something they are planning to correct anytime soon. They do claim support for v.24, except as it relates to multiple artists and null separators. Emby dev said they will put it on their list to come up with a fix for it but they don't plan to move away from ffprobe, in general.
The Artists (virtual) tag is interesting b/c ffprobe DOES read from that tag correctly. I just can't set it in MB. Right now I'm using Tag Scanner to Picard to set Artists but it's manual process so I'm still looking for something a little more automated.