How so? What would Latin America look like today in the counterfactual scenario where the Spanish didn’t colonize it?

The Meso-American civilizations routinely engaged in human sacrifice. Tens of thousands of people per year were murdered. These weren't peaceful monks quietly engaging in scholarly pursuits. Even if you don't personally drag victims to the top of the pyramid and cut their heads off or hearts out, if you stand around and watch, you're part of the problem. I'd be interested in how you compare the details of what pre and post colonization looks like and why you weigh post colonization as evil.

The colonization of the new world was largely an immunological accident.

When meeting Europeans, 90% of the Americans would catch some European disease and die. This was widely seen as the will of god(s) by both sides. Often the disease spread faster than the Europeans, so when they got to an area most people were already dead.

The following conquest is seen as barbaric and unjust by us modern people. But for the people of the time, it was just how the world worked. The Aztecs would have been overjoyed to conquer Spain the same way.