Here's the thing, when Apple got rid of the floppy drive, they did it because it was a design problem. Just look at the big G3 All-in-one "molar" design that preceded it. It's beautiful in its ugliness, but Jobs wanted none of the bulky, asymmetric case design that was a requirement of accommodating floppy disks, CDs, and Zip drives. Jobs came in and put a stop to that kind of thinking. In the process the floppy, which was still in wide use and fully supported, especially in the PC world, was eliminated. One of the most widely sold items sold with the original iMac was an external floppy drive. Yet Apple obsoleted it. They did the same thing when they eliminated the DVD drive from their desktops, which was still in widespread use, and is likewise still supported to this day. The fact that Apple makes a DVD drive acknowledges that this is likewise not obsolete, yet they've done it as far as Macs are concerned. Now they've taken away the USB type A ports, also still in wide use and supported, and obsoleted it on the rMB. So just because something is in wide use and fully supported, doesn't mean it's not obsolete.
So now we're looking at the 1/8" audio jack, still in widespread use and supported. The iPhone and iPad have one, and as mobile devices it makes sense, especially since it's a legacy port pre-dating current technology. But of the widespread use of the 1/8" jack, how many people are actually using it on a daily basis on their laptops, or desktops for that matter? An iPhone is carried around with the user, and used close to the face, as is the iPad. But a MacBook, like a desktop is meant to be used in a stationary position, on a desk or table. Even standing up will likely pull a person's headphones out of their ears, much less moving away from it. Even if it's on one's lap, it means awkwardly relocating it and managing the headphone cables to move. A much more efficient solution for using headphones with a laptop, to the extent anyone still does it, is to go wireless. And if someone really wants to use a wired headphone, adding an adapter to use an analogue pair, is not going to add substantially to an already messy situation. So yes, with respect to a laptop computer, it's an obsolete solution. Moreover, invoking Apple's own design mandates, it's inelegant and wasteful of premium design space.