The disease aspects are inseparable from colonialism. Here's a quote from a recent survey on the matter [0] that describes the current understanding much better than I would:
The contours of Indigenous depopulation were shaped not only by disease but also by complex colonial factors including violence, forced labor, exorbitant taxation, malnutrition, and dislocation. Archaeology has shown that Native populations were not destined to be decimated but were made vulnerable through the policies, choices, and behaviors of colonists.
Diseases imo are empathized because they contribute to the body count and have an “act of god” nature to them. It’s an easier story than to describe a type of industrial genocide.
Read about the Mit'a system that was perverted by the colonial government to essentially improve the return on assets of the colony versus slaves or other means of cheap labor. It broke down the society of the native population completely and made it impossible for them to respond or react to disasters.