And those parts of the world aren’t buying $400 iPhones (which are more expensive in developing countries) plus Macs. They are developing for Android.

It looks like you may be out of touch with the global market

There are substantial portions of the world where median income per household is 10000USD or less: https://en.wikipedia.org/wiki/Median_income

And software developers make few times the median in such places.

Source: am developer in a country you describe

Do people who live there own an iphone or a macbook? If not, how are they developing for those devices?

They often take a bank loan to buy a Mac + iPhone for the whole office, and devs take turns working on it and programming on it. The Apple Account would be for one person ("the company").

That's where hackintoshes come in. Technically development doesn't require a physical device too. Of course, UX is likely to be kinda poor when working in simulator only. But that's how it goes.

In those parts developers ain't paid local salaries..