As at least one of the commenters there pointed out, decriminalization is not the same as legal recognition. In other words, polygynists today aren't asking for marriage licenses, they just want to not be punished. So "should polygamy be legal?" is the wrong question.
The author also suggests that living polygamously is to be avoided simply because tidying up inheritances afterward is too messy. As if none of the inheritance laws and customs in the entire polygamous non-Western world exist. The sheer thoughtlessness of this sentiment, whenever I encounter it, bothers me perhaps more than any vicious attack on polygyny. "Because I can't be bothered to find out what this polygamy thing is about, I'm going to stand against it," never mind the years of happiness together of which people are thus deprived, the families that are never born and raised to be part of the nation.