Just to pluck up a stray petri dish of an example, the first new Star Wars came out, and (who, me?) I loved it. The Force Awakens! My one big complaint wasn't that it rehashed old plot-liner (very close to a reboot of A New Hope), because I felt that fit. It's a trilogy of trilogies. There will be some recapitulation, otherwise it'll become too amorphous. A poem has stanzas; Star Wars now has a reboot built in.
No, I found the movie thrilling. And this redundancy aspect was a statement, too. New makers, same spirit. If a lot was the same, a lot was different. Anyway, that wasn't my complaint. Nor was the deus ex machina of the Millennium Falcon appearing early on. That said something like, "Ha, gotcha. You didn't realize the Millennium Falcon was part of the Force, did you? It is. Fate will not explain itself to you always." The plot hole improved the experience in meta. No, my biggest complaint was that certain little moments had become de rigueur. When the trilogy of trilogies was first outlined, did Mr. Lucas have any idea how many scenes would involve a Jedi (or Jedi to be) in a fight, arm outstretched, verging on vanquished, light saber pathetically far off, wobbling? It wasn't story parallels or special effects or the unexplainable, but these little tics that were now shopworn. You aren't rehashing old story when things like this happen. You're... a genre.
And that's what resolved the irritation for me. I read another interview with the guy who wrote the script with the director, and he talked very openly about the work of writing genre stories. He'd decided that Star Wars was a genre, and he was thinking about it in exactly those terms. Ah, I thought. Ok. That was intentional.
The next thing he said was what was most interesting. He said that genre doesn't tell you what story to tell. It doesn't tell you what your theme is, your point, your message. You can write a strict genre movie (book, song, etc) about absolutely anything. And that's the beauty of genre. It's like the form of a poem. A sonnet could be about anything you want.
In other words, the medium isn't the message. Right?
It is a metaphor. Your eyes are not two shining suns. Your eyes are biological material with lenses and photoreceptors.
And this unrolls tendrils especially when you think in Claude Shannon terms about what a medium actually is. A medium is something like a sheet of paper. Papyrus is one medium, vellum another, tapestry another, woodcut another, flattened and bound wood pulp another—all closely related. Sure, a sheet of paper could suggest all kinds of ideas to you, and there are ways you cannot repurpose a sheet of paper. But there is so much you can represent on or with a sheet of paper that you are almost unconstrained. The sheet is genre. You can make it about anything you want.
It's worth agreeing that medium, genre, series, form, and format are different ideas. But this actually feeds into the larger claim. If genre allows just about any message, then medium certainly does. McLuhan is right, of course: choice of medium (and genre, series, form, format, etc) is part of the message and imbues it. And the appearance of a new medium changes society, revealing natural hierarchies and possibilities previously unknown. But we also need to agree that all these nouns work as information channels in the brass tacks mathematical sense outlined by Claude Shannon. Genre—say "historical fiction" or "dubstep" or "televised golf"—is like a wire. It's a narrower wire than medium—say "podcast" or "magazine" or "plasticine."** But they're both wire-like, media, tubes of aether. And both work just like wires to carry what wouldn't be there otherwise, which brings options to sender and receiver.
**If you want to call these more expansive names like "recorded sound" and "print" and "sculpture," then so much the better. That strengthens the argument.