i think that, along with the sitar player are still interpolating. the notes are all there on the instrument. even without an instrument, its still interpolating. the space that music and aound can be in is all well known wave math. if you draw a fourier transform view, you could see one chart with all 0, and a second with all +infinite, and all music and sound is gonna sit somewhere between the two.
i dont know that "just interpolation" is all that meaningful to whether something is novel or interesting.
If he plucked one of the 13 strings of a koto, we wouldn't say he is just remixing the vibration of the koto. Perhaps we could say that, if we had justification. There is a way of using a musical instrument as just a noise maker to produce its characteristics sounds.
Similarly, a writer doesn't just remix the alphabet, spaces and punctuation symbols. A randomly generated soup of those symbols could the thought of as their remix, in a sense.
The question is, is there a meaning being expressed using those elements as symbols?
Or is just the mixing all there is to the meaning? I.e. the result says "I'm a mix of this stuff and nothing more".
If you mix Alphagetti and Zoodles, you don't have a story about animals.
Would you consider the instrumental at 33 seconds a new song? https://youtu.be/eJA0wY1e-zU?si=yRrDlUN2tqKpWDCv
It is like expecting a DJ remixing tracks to output original music. Confusing that the DJ is not actually playing the instruments on the recorded music so they can't do something new beyond the interpolation. I love DJ sets but it wouldn't be fair to the DJ to expect them to know how to play the sitar because they open the set with a sitar sample interpolated with a kick drum.