To me the most important part of high resolution files are the bits, not the sample rate. Here's some science:
A 16 bit file has a possible 65,536 integer values per sample.
A 24 bit file has a possible 16,777,216 integer values per sample.
More integer values equals less quantization error which means a more accurate sample and a possible better sounding recording.
Loudness wars have to do with misguided thinking, that the louder the music is played the better it will sound on the radio. The idea being that anything that sounds louder will get your attention more. But with digital technology you have a brickwall that you can not go over, otherwise you get terrible distortion. So, the obvious answer to this stupid idea is to put everything at the max possible loudness. So now producers are asking mastering engineers to do this, which is quite easy to do with today's software. And of course engineers like to eat and buy new gear, so they do it.