My contention is emphasized in your post. Why do you believe that because the audio signal output is zero's and one's, it's better? In fact, digital could be worse - depending on the quality of the output (jitter etc). I don't recall any labs tests showing the integrity of the digital audio output over lightning. If there is one, please point me to it.
But... the biggest thing of all is that the audio signal HAS to go through a DAC at some point before you can hear it. It's all in the quality of the DAC...and your amp...and your speakers...
What if your DAC sucks compared to the one Cirrus Logic, Apple (or whoever Apple is/was using for the DAC in your idevice? You get "lower quality" sound even though the output, from the idevice, is digital.
To sum it up, the digital signal will be converted to analog at some point before you can hear it! So please tell me why a digital output beats an analog out for sound quality alone? That's what you said, and I'd like to hear why.