I think that the reason the yardstick may also be obsolete is because unless we were listening to the recording as it was being made, there is no objective approximation to the real thing...
I play guitar and my family has many pro musicians, so we grew up listening to all kinds of stuff,,,and the environments in which the instruments were played, tuning, quality all became ingredients to what our brain uses to identify what we listen to, and to like it or not....So, if I grew up listening to pianos in more sterile rooms, without perfect tuning, maybe the best Elliot Gould CD may not sound right to me,,,same with any instrument. I dont use nails to finger pick,,,I am a steve howe fan, and I find using nails a bit sterile...I like the smoother pluck of a finger tip, so that affects how and what I enjoy...
Dont forget that even measuring sticks are made with inherent biases.
When I audition stuff, if it hits me emotionally, it must be because there was some quality that is familiar to me subconcously,,,that is why I hate a lot of the higher end setups, especially with JMLabs speakers...