It's always good to gain wider perspective. But those "ancient moral theories" existed in a time and place with which we have little familiarity, making them hard to adapt. And worse, their adapted forms already have outsized presence in our current world-views. They're often treated as if they were universals.

I'd argue that we'd do better considering a wider range of moral theories from a diverse set of current cultures. Asian, African, and South American moral thinkers get short shrift in popular culture (as do native North American ones). Some of those theories also have ancient roots, but on a very different basis from the European ones we have a hard time escaping.

Why?