How about "modern" Muslim societies where polygamy is still a thing?

Also: Just because you are married, and your wife gives birth to a child does not necessarily mean that it's your child :) Nowadays, with contraception and paternity tests available, the number of guys unknowingly raising another man's child is around 2-3%, but it was much higher in the past.

It's still very rare even in Islamic countries. Look at this map.

https://www.pewresearch.org/short-reads/2020/12/07/polygamy-...

It's basically just Afghanistan, Iraq, Yemen and sub-Saharan west African countries that have >1% rate of polygamy and only the African countries that have more than 5%. Not exactly the most stable countries.

There’s an argument that monogamy is a requirement for what we’d consider a stable society, specifically for that reason.