What I noticed is after about 3 or 4 hours (for me), I decompress and start feeling like a child on a road trip again. Time is kinda of just going by, you distract yourself. They serve food at good intervals and you eventually get of the plane.
To say the California->Australia part is actually not as annoying as the domestic short haul flights from NY->LA which is like being jam packed like a sardine with few amenities. International, even in the cheap section, was comfy enough and I even had leg room!