> Latin America isn't North America.
A significant part of North America is also Latin America, and vice-versa.
> There were large populations of agrarian peoples used as a workforce by the Spanish.
Therr were large populations of people virtually (and sometime precisely) enslaved by the Spabish as agrarian workforce; they weren’t always specifically agrarian (any more than any other preindustrial population, including the colonizers) before that.
And, yes, through enslavement and other mistreatment, they, and even moreso their pre-conquest identities and cultures, were often wiped out. Sure, there are some remnants and admixture with the colonizers and other imported subject populations; that’s true of the native subjects of genocide in the parts of North America colonized by the British and French, as well.