We have really gone deep if we are discussing packets and cables

My point was different (CCA via optical cable vs built-in or where differences will reside in DACs when most of them use chipsets from same companies). If we really want to hear
significant changes in sound for the better (and not subjective biases like level shifting leading to worse/ better sound or bass feeling better etc.), all things being at a fairly decent quality (Source, equipment etc.), the following "algorithm" should work:
1. Getting Ears cleaned by a doctor (not joking. would have been joking if getting younger to get back hearing levels was mentioned

)
2. Getting sound in room sorted (not applicable for Near-field listening). I heard a couple of expensive speakers sets in my house yesterday. The more expensive one by a margin sounded worse by a margin. Am talking of both being Rs.1 lakh + speakers. If I had a smaller bookshelf in Rs.30-40k range, they would have thoroughly beaten the more expensive one and perhaps the other "cheaper" one (because of driver & design differences).
3. Learning about music so that we can "hear" more music. This is the most difficult part but it is similar to any other subject - we can appreciate
more if we can understand more about what all is happening. I can still enjoy music and appreciate it, but am sure if I knew more, I would have heard more. This is also akin to hearing bad mixes in good monitors i.e. suddenly realizing that a so-called good FLAC format/ Hi-Res etc format was mixed badly in the first place!
All three above will have more impact than experimenting with parts of a larger system. As it is, in ABX testing, even experts cannot find differences between competent amplifiers with significant price difference, two good file formats etc.
A group of us were listening to some very good active monitors last month in a treated demo room. Even with fast switching through a preamp, none of us could differentiate between a 3" and 5" speaker of the same family. Of course the fact that music was not low bass heavy made a difference, but still....
If the goal is to enjoy experimenting with equipment, all this is moot. If the goal is to enjoy music to the best of one's ability, then it is relevant.
There might be few who can differentiate easily but that will be a minority. Someone I know can still listen as high as 17KHz. On the other hand, the best way for an average person like me to hear more is to learn about music not equipment.