It's not only the difference (or none) between 16 or 24-bit, but it's mostly about the quality of the DAC that is being used - in this case a very high-end one. Then again, it's been proven time and time again that the average person can't even hear the difference between mp3 or FLAC. Considering you'd also need proper high-end monitor headphones, i believe this is more about marketing, the brand and the pitch than i…
It isn't equivalent enough to real music, and the human auditory sensory perception and recall systems just aren't perfect enough to make accurate judgements in those test cases. When testing you end up looking for discrepancies you can identify with words and identifiable momentary observations, things like "I can definitely hear this passage the notes are more muddled together in the compressed file." But you miss so many things that show up as minor feelings of unidentifiable hunches. Of course, you could change the format of the test, but even still, "identifying" is not "listening."
Things you can not identify, or talk about, or remember, or form sentences about, can still impact your musical experience. Our ears and brains are complex, and the range of input that is perceived subconsciously is astounding. We accept this for vision, for taste, for emotions, for memory, but for some reason not for audio. The simple feelings that you can't put your finger on can be important to the experience even if they can't be identified. But if you start to talk about "realism" and "emotion" and "feeling," you are immediately blacklisted by the empirical measurement mafia.
There is so much truth to the fact that scientific measurements and empiricism are important in determining the decisions you make about your audio storage and listening. You shouldn't pay money for things you can prove won't make a difference, and there are so many things out there that fit that bill. But we shouldn't throw out entire possibilities of discussion just because they influence parts of our experience that are subconscious or unidentifiable in an A/B test.
Again, I'm not saying we should disregard scientific evidence, just that listening tests set a limit that might not be accurate. We're finding only things that can be tested, and many parts of the audio experience don't fit the test.
In this case, there are more bits down there, higher resolution at lower levels. It basically means you can turn up the amplification and receive more resolution regardless of amplified volume. But it also means you have more information, and that's worth something.