As opposed to "humanist vs animalist"? "Savage" is another old world that unfortunately has racist connotations. But these dichotomies do make similar points.

When I think of "barbarian," though, I think of the rebellious locals fighting back against the Roman Empire or taking advantage of its weaknesses. Calling conservatives "barbarians" might suggest that they're like the Rebel Alliance fighting against an evil deep state. That's how many Trumpians view themselves. Christian conservatives, too, would like to think of themselves as persecuted underdogs. So "civilized vs barbarian" might play into their rhetoric.