I don't believe we will ever run out of music in a realistic sense. He mentioned earlier in the video, quantifying digital audio into its binary components reveals an actual physical limit to the variation of that binary to store and produce sound is quite astronomically high: 2^211,000,000 but certainly far less if we limit our definition of "music" and length to up to 5 minutes.
Under those specific requirements there is still an incredible amount of music that we can possibly make for many many years into the future.
