To help put this into context for others here.
It's interesting to note that Aristotle's "virtue ethics" -- based primarily on this work -- have come "back into fashion" over the past few decades, after being largely ignored by philosophers for centuries as having any contemporary relevance. (I.e. you studied it for the historical value mainly, but it had zero connection otherwise to contemporary analytic philosophy.)
The two main strands of philosophical thought over the past few centuries have been deontology (best exemplified by Kant) which is that you follow specific moral rules ("don't kill", "don't lie", "keep a promise") no matter what, and utilitarianism (Bentham/Mill) which is "the greatest good for the greatest number" (divert the trolley to kill one person instead of five).
They both obviously have truth to them but are also deeply incompatible with each other. Aristotle's "virtue ethics" says instead that what is most important is one's character, and that a virtuous character comes from a balance of temperaments. For example, you shouldn't get angry all the time, but you also shouldn't be cowardly all the time. Good character means knowing the right times to take bold angry action, but also knowing the right times to stay back out of fear -- and that honing good judgment is the key to knowing when. Sometimes it means breaking a promise, sometimes it means sacrificing a greater good for another principle, and there isn't always an obviously right answer.
Thus the idea of "good judgment that can't be reduced to strict rules" is now seen as an equally viable alternative to deontology and utilitarianism. Perhaps because it seems particularly relevant in an age of relativism.
Also perhaps particularly telling, in the TV show The Good Place which recently ended, and where every episode is about a different philosophical dilemma, when the creater Mike Schur was asked about which philosophical system was closest to his own beliefs, he replied that it would have to be Aristotle's virtue ethics.
I personally found reading Nicomachean Ethics a fascinating experience, because it was written pre-Christianity, so the complete and utter lack of notions of "good and evil" is revelatory. We're so used to thinking in such terms in much of the world, it's refreshing to see a totally different worldview.
In case anyone is curious for a modern treatment of Aristotelian thought, Martha Nussbaum's book Upheaveals of Thought played a big part in "rehabilitating" Aristotle in contemporary philosophy. It has parallels to the vein of "emotional intelligence" that became popular a few years earlier.