Sorting lists oldest-first is just one of the ways I am strange and different to the world. When it is available at all, it is not the default. Almost everyone else in the world seems to prefer to see the most recent items on top and others after. This affects Quickflix, Facebook, YouTube, Pocket, Feedly, almost anything that has a list of anything, actually.
Quickflix, for instance, made the decision to have new titles added to the top of customers' queues, rather than the bottom, because most of their customers preferred it that way. I assume this is because most of their customers were confused by the way a newly-added title would not appear to be in their queue at all (it was at the end, where they didn't look), or because people are all impatient. It also means that you can't add, say, Robocop 1, 2 and 3 in that order to your queue, or else you will receive number 3 first and be too disappointed to watch the others.
I wonder at the core mentality behind this preference. Is "first" the only place in line that matters? Yeah, probably, come to think of it. Do people have no patience to view things in the order they were discovered, rather than getting everything RIGHTNOWRIGHTNOWRIGHTNOW? Primacy and recency are now the same thing. There is only "what is happening right now" and "irrelevant haze". I guess I find it a little sad if every moment of your life points to the present, whether it's in the future or the past. There is bright, loud, demanding NOW, a hazy who-cares yesterday, an uncertain, figure-it-out-later tomorrow and NOTHING. This is what it looks like to "live in the now". It is impatient, unfocused, oversimplified, demanding. A frantic pace of staying still. The world clamours, and we vibrate in time with it, because we are passive observers of our own lives, and then we die.
Okay, that got depressing. In a nutshell, queues are a tool of patience and stacks are a tool of information overload.
Imagine if it worked this way in real life. You're standing at the cafe waiting to be served, then someone else arrives, so they go to the head of the queue, get their coffee and leave. You are still, say, fourth in line. Now two new people arrive. One gets her coffee and goes, then the other makes his order, but in the meantime, two more people arrive. Now you're seventh in line. You're better off leaving and coming in fresh to get to the head of the line and be served first, screwing over the other guys in front of you. A stack is a terrible way to get through everything, though it makes no difference to the barista.
Mokalus of Borg
PS - When dealing with your own playlists and news feeds, in this metaphor, you're the barista.
PPS - Also, your customers can't get mad, because they're inanimate.