Apostate prophet wants social justice; Islamic polygamy is mysogynistic?

In answer to the video "10 Reasons to Reject Islam"

4:3"And if you fear that you cannot act equitably towards orphans, then marry from the women that seem good to you, two and three and four; but if you fear that you will not do justice between them, then marry only one or what your right hands possess; this is closer that you be just".

Contrary to popular opinion, the verse is not addressing the issue of polygamy in a general sense, a pre-existing practice, but that of polygamy in a narrowed down context, that of safeguarding the orphans' rights. The reason the Quran only speaks of and limits polygamy in that context, is because these types of relationships hardly if ever run smoothly and therefore should be reserved for the achievement of higher objectives.

It is clear from the opening statement, positing the situation of one with orphans under care, fearing for the just management of their rights

4:3"And IF you fear that you cannot act equitably towards orphans, THEN marry..."

The verse is therefore silent on polygamy in a general sense, neither allowing nor forbidding it, but by only mentioning one case to which it applies, clearly hints to the preferred way to apply the practice, moralizing it, laying down the basis for the intricate perspective that must be considered if a man wishes to marry more than one woman.  However it is to be noted, this doesnt mean that polygamy outside the context of caring for orphans, which is the subject of the verse, is useless.

Outside caring for orphans, polygamy can potentially be an answer to many problems one can think of, so to outright ban it would deprive the believers from a solution to potential social difficulties. Women around the world, not necessarily in Muslim societies are confronted to situations where they are left to fend for themselves and their children without the help of the family or the support of a father. But because polygamy is regulated and moralized in the Quran, by mentioning only one case to which it applies, along with its conditions, the Quran is explaining to the God-conscious that this familial configuration is not to be abused for selfish motives, the gratification of sexual desires.

There will always be people that will take advantage of the system, just as there are Muslims that will disregard that limitation to make it subservient to their own whims. Polygamy is thus not the norm but the exception in Islamic societies. It is a license granted to men to alleviate problems that have existed and will keep on existing in human societies.

From a modernist perspective, feminists often denounce the practice as legalized cheating. 2 things dont become the same because of superficial similarities. Is a regular marriage legalized prostitution because a man gains sexual access conditionally to spending from his resources? In a marriage, there are many more implications, rights and obligations beyond sex which is just one of the rights of both parties on another. A feminist may now be tempted to say that a wife is just a long term prostitute with more rights and duties. But then is any unmarried woman that has sex with a man prostituting herself because, besides money, there always exists an exchange without which the man would not have sexual access, including emotional, physical, intellectual etc. attractiveness? This extends to lesbianism and on a deeper level, even to self-sex where a woman is essentially a prostitute to her desire. 

Feminists see genders as conflicting opposites rather than completing one another. This is why they loath systems that bind genders together whether monogamous or polygamous. They will prefer situations that paradoxically oppress them, like prostitution and adultery, because of the limited rights the opposite gender has on them in these cases.