I'd be fine with polygamy if it weren't (1) forced, (2) forced on kids, and (3) polygyny only, disallowing other options such as polyandry or same-sex unions.

The fringe mormons are some sick evil fuckers, but I don't care for the tone in that article (and elsewhere) that polygamy is inherently abusive (any more than arranged, guy-in-charge monogamous marriage was representative of all monogamy, or the absence of laws against marital rape in most states til recently condemned heterosexuality). Forced marriage, child rape and child abandonment are abusive, no question whatsoever.