For me it’s partly population size, but also like… Culture/global impact i guess? Rio/Sao Paulo are some of the biggest cities in the world, and a part of one of the biggest countries in the world, and they’re both “brand recognizable” names.

Beunos Aires, Toronto, Chicago, Huston, Havana and maybe more in Mexico/South America I can’t think of off the top of my head will round out the top 10ish