You may wish to reconsider your hypothesis after viewing this chart:
https://ourworldindata.org/grapher/children-born-per-woman?t...
https://ourworldindata.org/grapher/children-born-per-woman?t...
Everything is expensive as hell these days.
Interesting to see the fall in the GCC countries like Saudi Arabia, UAE, etc. The charts show them at ~2, even though those governments actively provide subsidies for citizens to bear more children. iirc they used to be MUCH higher.
Have an Emirati friend who has 5 kids on a government job (he lives with his parents, as is expected culturally, so that obviously makes a difference).