I'm not sure ... are those two sentences kinda counter-posed statements ?
Alternatively, realism is the most potent single descriptor in that it is the aggregate of the positive characteristics that make it up. But realism does not need to be parsed.
We hear the analytics say "in order for a system or component to sound realistic it must provide X, Y and Z". I don't think we need to try decomposing the experience in order to either a) have it, or b) understand what it means when someone says "that sounds realistic".
Attending a live acoustic concert, realism doesn't enter our descriptive vocabulary. We don't say the orchestra needs better transparency or more defined bass to sound realistic. We know the way things are.
Likewise I am inclined to say realism is the simplest and most direct character one can ascribe to a reproduced performance, or not. Granted, as
@PeterA says - and I agree -- when lstening to our stereos, there are degrees of realism. We can attempt to explain what leads us to ascribe realism to it or what is missing by using audiophile attributes as an analytic exercise, but we don't need those in order to have or not have an immediate recognition of it.
Not sure if that was word salad. There is listening and then there is 'audiophile listening'.