Can´t export DNG files from the iPhone

yup. The 4:3 is the native ratio of the iPhone’s sensor. That was the first epiphany. Frankly, the image quality of the native 4:3 sensor output exported as ProRaw and processed in LR on the laptop is amazing. “ I have several camera systems but none are as convenient as the iPhone 12 Pro Max. The best camera is the one you have with you.” The second epiphany was to persist with escalating in Apple Support until I reached a Senior-level support person.

Oh, I completely agree. I took a shot outside today where the sky had nice faded blues, but the photo I took was over-exposed. Popped it into PS with the Camera Raw option and sorted that out with ease. I hardly had to do much to the photo to save it as opposed to what I would normally need to do with a DSLR. I came from the X to the 12 Pro Max and the difference is 100% better than I had hoped. As per your second point, I chuckled :D

Since a 16:9 is actually a crop, not all of the sensor photo sites are used because they are arranged in a 4:3 matrix. Perhaps their algorithm that does the computational magic behind ProRaw is only applied to the full sensor. Just a guess.

When I connected the iPhone through the USB cable to the computer and accessed the files, the RAW files in 16:9 were like 30 MB size, but I couldn't manage to copy and paste the files since the iPhone got continuously disconnected from the computer. I guess that those 30 MB files are DNG format.

THANK YOU! I also found the .DNG photo inside the Photo app Originals folder, but your steps are much more elegant

It would have be great to be able to open the DNG-file directly in Photoshop/Lightroom on the iOS device while on the go.

That seems to be correct. I've tried other ratios like 16:9 and it exported as jpg...it's a shame!!

I have the same problem with USB export in Windows. You give me hope that the DNG files of a few of my favorites exist although they have eluded me so far.

I just tried that. The photos are getting converted to JPG, so that's not a solution

The Apple document that teaches: edit a ProRaw then revert and airdrop to send a .dng does not work. My guess is Apple does not want customers sharing ProRaw .dng files from the native camera app that are unflattering without additional processing.

Same problem. Both the Halide and Moment apps will export .dng but not the native iOS camera app. The native camera app will airdrop or email only .jpg. Apple support seems to be unaware.