Gorillaz - Gorillaz - Deconstructing Genre

That wasn't the point of that graphic. Every genre in that list has a ridiculous amount of subgenres. There'd be no point in listing all of them and it wouldn't even fit in the video. The point the author makes would work just as well with generic examples like "Main Genre A" → "Subgenre 1", "Subgenre 2", "Subgenre 3"… but this way is more relatable for the audience. Don't get upset over nothing.

"A look at the animated band that blurred the lines between genres"

Intentional or not, that's amusing.