Yes, and you could buy a floppy disk drive very cheaply too. Nobody uses those anymore either.
What a ridiculous comparison. Floppies were limited in their design capacity, and Apple's decision to start phasing them out in 1998 (I believe) was ALSO premature. Why? Because there wasn't a good alternative on the market yet for those who needed to transfer files. Zipdisks were fine, but they were pricey, buggy, and annoying. CD-ROMs were write-only. CD-RWs were unreliable and often unsupported in some readers. It was really the USB flash drive which finally replaced the floppy, but that didn't come around until 2000. Once they became cheap and popular, most computer companies finally started dropping floppy drives.
On the other hand, lots of people complained about Apple's decision to drop the optical drive on the MacBook Air, but I thought they were behind the times on that one. I've been using laptops (ultraportables) that didn't come with an optical drive since 2005. The reality is if you wanted the lightest, smallest laptop, why would you carry an optical drive around with you?
And yet they are still useful periodically, so when I built my current desktop, obviously I put an optical drive in. The choice is for a specific use case -- you want the lightest thinnest possible thing, why not get rid of something bulky? You could always buy a USB optical drive, which I've been using with every laptop I've had since 2005. For bigger laptops ("desktop replacements"), an optical drive can still be useful depending on what you do.
So digital audio to the speaker is the future, and then it might as well be wireless. Or you'd have to define a new physical connector which supplies power and a digital signal.
What the heck are you talking about? Why do you think you need to replace the physical connector to get the advantages in digital signal you want? You can ALREADY buy a bluetooth headset and use it with current technology. Your argument doesn't make any sense -- "There are some things that you can't do with the analog audio connector, and if you wanted to do them that way, you'd need other complicated things." NO -- if you want those things, you just buy BLUETOOTH now.
The only difference Apple's decision here makes is that we're all forced to buy more expensive tech to do a rather simple task. The vast majority of people don't care about the audio things you're talking about -- they listen on the crappiest set of earbuds they can buy.
Except now you want to force them to bulk UP those crappy earbuds with a battery and a Bluetooth connection.
Frankly, I don't want to have another device with batteries to deal with. It's already enough to worry about to plug in my phone and tablet to charge. Now I need to be ready to replace the battery in my headphones or charge them too?
Sorry, but even if the cost for wireless was similar, that's just too much of a pain for little benefit. To me, it's the same as wireless mice and keyboards. I bought my first wireless mouse in 2005, I think. It was cool for a couple weeks. Then I had to replace the battery. Then I decided it wasn't necessary. I've never bought another wireless mouse or keyboard since. If I had a specific use case where running a wire was annoying (e.g., controlling a TV across the room or whatever), then sure, I'd use one. But I don't need to have a wireless mouse to "declutter my desk." Dealing with batteries is just annoying unless there's a significant tangible advantage.
Same thing with this headphone thing. I'm not going to deal with batteries to power my headphones unless there's a real advantage. I do actually have Bose noise-cancelling headphones, which are awesome for when I use them, and yes they require batteries. But that's for a use case like airplanes where there's a real advantage. On a daily basis if I'm out for a walk or whatever, I don't want to deal with my battery in my earbuds going dead... just so Apple can shave another fraction of a millimeter off the thickness of its devices. (And of course, that's not the real reason -- they want to see you buy some expensive connector or other peripherals.)