Emerging markets don't buy small cars as a conscientious environmental decision, they buy them because it fits their budget. Small cars cost less than large cars to buy and run.

Emerging markets actually have newer roads in comparison to developed markets.

Flawed logic, most emerging markets have new road infrastructure only around main arteries and large city connections.

Unfortunately also road construction quality is lacking because of low budgets and/or corruption leading to faster degradation, often new roads are heavily damaged after a few rain seasons.

In the capital cities - maybe. But outside? You can travel on street view to Egypt or Russia, there are bad roads and no off-road vehicles.