This argument is the same over and over. "I don't need ______ so I don't understand why anyone else does." Good Camera on a phone, Aux jack, SD card slot, whatever. The fact is, I have several different sets of headphones, so will I need an adapter for each? What will these new adapters cost? That is an added expense that I didn't have before. And you are making an assumption that the adapter available on HTC.com is the same one that will be released with the U11. I doubt very much that it is, and expect that the new adapter to cost upwards of $25 each. The DAC isn't free.
Then there is a question of signal amplification. Does this new set up drive the same impedance headphones that my 10 does? Will I now need to buy an external amp to run my high-end cans?
The new adapter with the DAC draws power from the device, so you can't leave it plugged in while not in use. That wasn't the case for leaving headphones plugged in. On that same thought, what will the impact be on battery life? Negligible? Significant?
If BT was the future of how audio is to develop, how come the U11 doesn't use 5.0? How come it doesn't support AptX HD? What if I don't already own BT headphones? I don't. So another added expense. And those have to be charged, and over time, the battery degrades, so, there is that.
If audio over USB-C is the future, how come the audio industry doesn't offer a deluge of USB-C alternatives. Especially on the higher end? Because they would have to make one version for Lightning and one for USB-C. And the onus would be on the manufacturer to install and tune the DAC in their headphones. Variation may be SIGNIFICANT from manufacturer to manufacturer, moreso than just headphone quality.
What about people who own cars without BT connections. Buy an additional adapter or a BT rig for the car. Added Expense there. And if the car does have BT, is it AptX? AptX HD? What about signal interference? And what happens when it just doesn't work. I know this isn't obvious, but auto manufacturers are WAY behind the tech curve. I wouldn't be surprised if most cars are only BT2.1 ADP. And then there is the issue of cars having a much longer life span than phones, so as technology marches on, we are stuck with phones that don't even work with our cars in 5 years. What happens when they abandon BT for a new tech? Progress.
The question was raised in a post above, what is the BENEFIT of removing the port? Thinner device? We are at a point of ridiculously thin devices now. Not to mention, many phones are housed in bulky cases these days. Larger Battery? That isn't the case here. A larger screen on a smaller device? Not the case here. Simplified design? I don't see that here. Water proofing? Not according to Samsung, who still offers the Aux Port. Cost? Laughable. So some of us have to give up a convenience and potentially increase a cost for what benefit? I didn't think it made sense when Apple did it, and I don't think it makes sense now.
And to argue that headphones with active noise cancellation somehow improve audio, that is simply not the case. The audio signal is significantly processed and much detail can be lost in sloppy applications. It may improve the experience (especially on flights, where Bose NC headphones are extremely common) and remove noise, but it doesn't actually improve the audio.
These are the reasons it annoys me, and I find it to be an inconvenience. In the end, we will all have to face the extinction of the Aux port, but I am invested in it and I am not quite ready to go there yet. For folks like me, this will be an unwanted loss for no perceived or actual gain.
I hope this answers your questions. Feel free to flame on.
~Ex