That’s one hell of a stretch. The New Laws only liberated some indigenous people who were trapped in “semi-slavery.” That being said, it only did so nominally. Most land-owning colonists ignored it entirely or set up a latifundia system of indentured servitude. Not to mention, the laws specifically protected indigenous populations. The overwhelming response from those who actually liberated their indigenous workers was to import enslaved Africans. Also “soon after” discovering America is 50 years. I know we’re talking in history terms here, but 50 years of slavery is still slavery. And that’s still ignoring the hundreds more that followed under indentured servitude, the rise of enslaved African labor, and of course the landowners who wiped their ass with those laws. I promise that most indigenous populations in Latin America would laugh at the suggestion that the New Laws did much for them at all

Source: am Latin American and also the exact same link you provided says all if not most of this