RA theoretically is fine with descriptive labels, just not prescriptive. However, there are people very into the politics of anarchy who do not think it's compatible with monogamy per se. To them, it's more than a way of perceiving relationships. It's anarchy given form in interpersonal interactions. So, when you say monogamy, they'll hear "forced monogamy, possessed against his will". There's a version of monogamy in RA, but it's untraditional.