One of the most strongly-held arguments about Apple removing the headphone jack is that Apple has historically been first to drop a legacy technology, sometimes even before the rest of the industry is ready. Apple’s vertical integration, passionate userbase, and scale (both historically small and now immensely huge) allow it to push big changes in a way that few other companies can pull off. The floppy, SCSI, optical drives, VGA — all killed by Apple years before vanishing from the rest of the industry.
Excellent number crunching. I still think the headphone jack is not the same as SCSI or VGA. While a standards body may have invented the headphone jack 70 years ago, that body is long gone. Most standards that define things like USB, FireWire, SCSI, HDMI and Floppy Drives have a vested interest in keeping those technologies alive or bringing vendors to the new standard when they’re ready with one (USB-C for example). The headphone jack is everywhere and if you buy the most expensive audio doohickey in the world today, it will come with a headphone jack down to the cheapest pair of 99 cent headphones. It’s a standard that is not going away even if Apple chooses to abandon it.