I have been wondering what's the actual status of iOS updates outside of the US, or in countries where nobody uses wifi? I just checked that my SO's iOS was on 16.3.1, over 2 months old iOS version.

Apple has decided that iOS should only accept downloading OS updates over wifi. In my country, for example, people don't really set up wifi at home anymore because basically everyone has unlimited cellular data. So they don't need to connect to any wifi at all. All the iOS update statistics seem to come from the US, where everyone relies on wifi.

It seems that on some level, iOS suffers from the same update problem as Android, but only because Apple decided to do so for no reason. Not everyone lives in the US.