Everything is relative. Take, for example, scoring 20/20. For eyesight it’s considered merely normal; for wine it is anything but. Furthermore, vinous quality is assessed in a subjective way, whereas visual acuity uses an objective scale with de facto conclusions – for instance, 20/200 is considered legally blind, while NLP is the most severe classification of blindness, 'no light perception'.
Similar, if perhaps slightly crass, distinctions might be made between the rigorousness of blind tastings – some are decidedly less opaque than others. As for the objectivity of scoring wine, I side with those who posit that it is essentially...