I don't know where you get the idea that Macs can't play 1080p high bit rate (Blu Ray) but you are right about HD audio although it has been confirmed that you can't play HD audio with Macs even in bootcamp.
You are wrong!
I have a 2011 Mac mini and I can 100% confirm that under bootcamp I can bitstream hd audio to my amplifier. You must be running powerdvd or similar software to pass the audio but it works. Also another point, you can pass full frame (1080p per eye) 3d video under the same configuration.
Cheers
James