ok ok i think we've been over this many times: youtube is meant for watching videos with audio, not just listening to audio. if you want to just hear the song use a website like www.youtube-mp3.org
This is not a technology issue. Obviously such technology has existed for probably longer than you have been alive (judging by the fact that this would even matter to you). If you aren't impressed with what technology can do today, you either don't know what technology is, or you are oblivious to the amount of technology around you every day because you take it for granted.
Youtube was never meant to be a music player. Use a music app if you want to listen to music. This has nothing to do with technology, but people using the app in a manner it was not intended to be. This is like me saying "I won't be impressed with technology until my calculator app tells me the temperature". Also, as mentioned, some devices do let you; it is about the app coding.
We can Submit footage and sound, alter qualities to make it run smoother, but we cant do something simple like listen to it without closing the app? Bruh.
yeah you could but then YouTube took away that feature stating that there were copyright issues caused by it, I'm not really sure what actually happened to make them get rid of it.
This is not a technology issue. The technology for this is very simple. The sole reason that you are not able to do this is because YouTube makes money off of the ads that run before/during their videos, and you can't see the ads if the app is closed. So, they make sure the app has to be open in order for you to listen to whatever it is you want so that they can bombard you with ads and make money off of this.
It's not being limited, it's just carrying out its function