You typed a really long comment, but you're not talking about the same thing. Listening to an ad before a song starts is very obviously not part of the music, even if it's part of "the experience of listening to music (on a streaming service)." The ad before a song plays is not included in the song's official runtime.

You're essentially describing the time the audience sits waiting for the orchestra to walk onto the stage as being "part of the experience of going to the orchestra." Which is fine, but it's not considered part of the song (unless the composer's quirky and writes "walk onto the stage" at the beginning of the music sheets, which is basically what this guy did with the 17-month rest).

Moreover, nobody was actually sitting in that cathedral for 17 months listening to the first rest. If a 17-month rest is played in the middle of a forest and nobody hears it, was it really a 17-month rest? Who experienced that "experience?"