I disagree with your denial that European disease caused the rapid depopulation of the Americas. South and central American cultures had certainly declined due to overpopulation but they were still at the limit of their population which is part of why they were so vulnerable to disease. It also appears to be a case of very bad evolutionary luck, as compared to the effect of syphilis on Europe, and as you say, certainly not a premeditated attack by the Spanish. 1491 by Charles C. Mann is good on this topic.
I disagree with your denial that European disease caused the rapid depopulation of the Americas. South and central American cultures had certainly declined due to overpopulation but they were still at the limit of their population which is part of why they were so vulnerable to disease. It also appears to be a case of very bad evolutionary luck, as compared to the effect of syphilis on Europe, and as you say, certainly not a premeditated attack by the Spanish. 1491 by Charles C. Mann is good on this topic.