1) Part of what seems quaint/dated about it are its "abstract qualities"--the delayed and overlapping voices sourced from television and radio broadcasts, while a perfectly standard tool in this kind of music, feel like a sound from another era. Radio and television are obviously still a thing in today's world, but it doesn't seem like the kind of polyphonic/chaotic stream of voices and languages pouring into our consciousness primarily comes from television (and not at all from radio). From the graininess of the voices to the very conceit, the piece feels profoundly pre-digital in a way. The echoes of Boards of Canada's aesthetic in the first section are another example--that sound was meant to recall a specific material reality of the pre-digital world, the warping of tape and video by time.
2) The ascent of Glitch in the early parts of last decade (via compilations like the Clicks and Cuts series on Milles Plateaux) seems like a moment of transition into some new conception of abstraction in a digital age, one that has perhaps blossomed fully in the last few years via things like Oneohtrix Point Never's music and the New Aesthetic (and that had already started to come into existence several years before the millennium via time-stretching in jungle and drum'n'bass).
3) Another sign of this transition might be Brian Eno's albums for Warp, Small Craft on a Milk Sea and Drums Between the Bells, which work in much the same way as his work in a certain kind of pre-digital abstraction (Discreet Music, the albums with Fripp, Bowie, and Cluster, the Ambient Series, Apollo, the Windows 95 theme, etc., etc.), but do so in a showy and frustratingly obvious digital way--each glitch feels designed to call attention to itself as a glitch, as if just to show that Eno has in fact listened to electronic music produced in the past two decades (needless to say, I'm not a huge fan of either of those albums). This also plagued his most recent album with Fripp, though not quite to the same extent (and at times actually wasn't a plague, but made for some quite lovely music).
4) Perhaps another example: the difference between the lines drawn in this list by Mark Richardson and this list by David Bevan about the manipulation of the human voice in music. That Burial and Four Tet are the common denominators seems possibly interesting (a sign of the apparently diminishing-in-value quality of "importance" in their respective musics?).
5) As a related thought on abstract qualities/pre- and (post-)digital abstractions/etc., Ghost Outfit wrote recently, in a piece on Richard Taruskin's The Danger of Music and the necessity of music having an explicit connection to human issues in order to avoid "formalist sterility:"
I still think [Tim] Hecker's music is great but its beauty exists entirely for and of itself. It isn't concerned with the human and, despite all its shimmering construction, suffers from an emotional blankness--a tabula rasa whose sound is gorgeous and unearthly but doesn't relate with the world outside it.
To an extent, I understand where such a reading of Hecker's music is coming from--its emotional content is often ambiguous at best and his catalogue's studied abstraction coupled with this seemingly emotionally distant/reserved nature has led some to call his music academic (read: formalist and sterile)--but I disagree. While I doubt anyone is finding his or her tales of personal tragedy/redemption echoed in Hecker's music the way that he/she might in the music of Xiu Xiu, Momus, or Wild Beasts (to pick the artists Ghost Outfit contrasts with Hecker), I think Hecker's own comments about his music suggest an equally real connection that his music has to the human, to the world outside of itself. His repeated invocations of secular church music is perhaps the big clue to how he conceives of this interaction, but I think his music also connects in its digital/(post-)digital abstract nature. Hecker's music in some ways reflects and in some ways reshapes a digital consciousness--this is attention as snow and static, lost and damaged transmission, corrupted files, bad data (it makes sense he would be obsessed with what he calls "digital garbage"). It's the beauty of those aspects, the way that their drone and thrum form not just a background of our lives, but a significant aesthetic component of them that can be equal parts beautiful and terrifying.
6) Like the Jameson essay I referenced in my review of Evian Christ points out, though, the present, this (post-)digital realm, is unavailable to us. We cannot experience it directly. What makes "Duga-Three" so affecting, then, is not just the emotional pull of its elegiac tone, but the way that its reminder of another kind of consciousness, another form of abstraction (and I think the formal elements are key here), also allows the present to be set off in relief and experienced. Similarly, in his rendering of those elements that make up the backdrop of the digital world/consciousness into reflections on the very process that turns them into works of often profound power, Hecker's music also makes the present available to us. I understand the moment in which I am situated--and the way sounds function in the spaces of that moment--better because of Hecker's music. I find it "vital, confounding, and powerful" (to use Ghost Outfit's criteria) in equal measure to almost anything I can think of with lyrics.
7) All of the above points in 5) and 6) about why I find Hecker's music and "Duga-Three" so powerful seem related to the shifting sense and experience of time enforced by late capitalism, as outlined by Mark Fisher here.