Why on earth?

What you get is a crude combination of the characteristics of your playback system and room acoustics layered on top of a crude combination of the poster's system and room acoustics, plus the very crude characteristics of the microphones employed and recording techniques, etc.  It is ridiculous to then try to isolate the difference one piece of gear makes in this mess.  A friend of mine toured a recording studio and was shown a room full of microphones.  There are some artists who will request a very specific microphone--not a particular brand or model, but a particular microphone because the difference matters to the artist.  Do you think any of these posters have that kind of selection and special microphones to capture the essence of the gear being auditioned?

The testing folks are also a bit unrealistic.  They often post frequency response, waterfall plots, etc. of speakers and comment as though those tests give definitive results.  Wholly apart from whether the tests really measure what we perceive and like, the tests themselves don't accurately measure what they purport to measure.  Manufacturers looking for good measurements send their gear to a testing lab in Washington state that is built inside a nuclear reactor facility that was never commissioned.  The main testing room is behind many feet of concrete and the room is gigantic (something like 450 feet long and wide).  The testing facility certifies that it can accurately measure speaker frequency response down to 25 hz.  Now tell me how some backyard or garage setup can give accurate measurements.

Generations of yoots loved the sound quality of mp3, those golden ears are still out there, they hear differences we cannot possibly hear. They can probably hear the magic difference of various fuses in equipment online.

A very good question your phone,or tablets monotone speakers suck!

the only thing I can see is showing you features or the design and components 

which have some merit, as far as music 🎶 it is a moot point ,pointless literally !!

Dog breeders post videos of adorable little puppies, frolicking around doing "puppy stuff" as if an amateur video will incapsulate a valid representation of the essence and personality of the puppy. Some people have the ability to visit the breeder in person and conduct a 20-minute "personal interview" with the prospective new (long term) roommate. Some order these furry creatures sight unseen not knowing if they are getting a cuddly ball of joy, a family treasure, or a narscistic little bastard that’s all about his own gratification that could care less about the emotional needs or time constraints of its new owners.

I guess people who love puppies, are lot like people who love audio gear. Any morsel of an interaction that comes from the experience (via YouTube), regardless of how limited or compromised is better than no experience. "..... I sure would like a hit."

Atleast picking the wrong DAC won’t poop on your floor, be a time vampire, or chew thru your internet cable.

And, oh yeah, the grandkids love the puppy. And the internet is back up and running.

Okay, we went for a cruise in one of my old cars yesterday with the top down and his little puppy face hanging out over the door with fur blowing in the wind. We’re good buddies now. Nevermind.