In Islamic societies, men having multiple wives was quite rare, with the vast majority of marriages being monogamous.

It wasn't driven by having less men. It was driven by the upper class wanting more sex.

It also turned out to be disastrous for society, and most of the Islamic world has outlawed or severly restricted the practice as it leads to huge social problems.

The fact is that war has never been a large driver of casualties in these societies, outside of WW1 and WW2 which are the two exceptions and really don't prove your point. Wars were never fought to protect women, and most men died of disease and accidents, not war.

Polygyny was not restricted to Islamic societies though, and was a common occurence accross many societies. It was always restricted to a limited amount of men of course, as only the most successful/powerful/whatever could afford it. It does have heavy social consequences, but those might or might not be an issue for a given society, as some were quite successful (ie surviving for a long time, no moral judgement here).

I certainly agree, the analysis applies to all other societies, but the link in the post was specifically about Islamic societies.

My main point of contention was that it wasn't a widespread practice and wasn't motivated by a lack of men.