yes the reason they dont sell out arenas worldwide with those "beautiful sounds" is because peoples brains are not trained for that level 
Pretty much that. Most people listen to quite a primitive music and lack capacity to process sounds of a high complexity. Many people can't undersand the music that I listen to, but my parents used to take me to places where jazz/classic and alternative music was played from a very young age. Later on I just couldn't get a "hard" on simple sounds, just too simple, brains doesn't release the "happy" chemicals as they are not being used to a full capacity. It's difficult to explain for someone who does not have that kind of education, but if you were - you would enjoy the sounds in that vid a lot, trust me.
And just like everything that is worth having - it takes effort (and masses doesn't like effort). You won't be able to appreciate classical music (for ex.) from a get go. You will have to WORK to figure out these patterns, over and over, over and over, and then.. one day you will say "Give that shit to me, bring it on!" and laugh at the "music"that you used to listen to. It's always like that.
