Though I have never seen this video, I have to disagree with you. In every decade people talk about music being worse and stuff like that. Then years ago people were asking the same question.
The thing here is about what kind of music you're talking about. If it's about mass-oriented music, so yep, they have the same structure according with their genres.
But if you're talking about something much bigger, something that extends to all kinds of music, then definitively there's a mistake in thinking that in the future all songs will seem similar.
As you said, there's a infinity of combinations and sounds, melodies, and I must say that technology is helping a lot in this situation, creating even more possibilities.
Every artist, from a painter to a writer, from a dancer to a musician, tends to copy what they have learned from other people, such as their masters or their "idols". But there's a misconception here, because using something that you learned from other people make a certain model for what the artist is supposed to create. He/she simply follows that model, and that model can be re-shaped, updated, it can merge within another model, etc. Thus, even if they follow a model, this model is much like a Ditto than anything. But this really depends on the artist him or herself and their ability to express their feelings in a structured way but at the same time in an individual way.