When one travels between cultures one realises that there is no single way for a medium to be. The medium shapes the message, but it does not determine it. It is only cultural habit which says that television should consist of rolling news or of an over-stimulating mixture of reality tv, soaps, sit-coms and makeover shows. DVDs can be used for things other than movies and porn. Songs can last for more than three minutes and not have 4:4 beats to the bar and they can be about subjects other than violence and sex.
In the West, our primary genre is entertainment. We use our media to amuse and distract us. The media are the opiates of the people.
Elsewhere the very same media are used to inform and educate and to indoctrinate and inflame. The back-story of British Asian terrorists always mentions dvds of western atrocities. Soviet television was notoriously humourless and doctrinaire. You only have to skip through the internet to find an alien and intimidating bredth of human thought and expression.
So I would update McLuhan and say “The genre is the message”.
Or maybe I’m missing the point.