various Latin LCAs
I don't think that Vuelamex ever flew. But Azteca does, with lots of trans-border into the USA. In fact they just announced new flights GDL-ONT today. You could also check the pricing on Aviacsa which does lots out of MTY.
The Argentinians that have tried loco have gone bust. LAPA, which evolved into AirG is gone. And the devaluation of their currency didn't help.
GOL is the first and has done well.
Their populations just don't have the incomes to fly enough to support the proliferation and the great distances are also a detriment.