How do we interpret this heartless-sounding statement? In the absence of original source material, whatever interpretation you apply will inevitably be a projection of your pre-existing views on the matter. If you want to knee-jerk your way to the standard "Goldman Sachs is Evil" view, help yourself to the rest of the top-level comments in this thread. If you're still reading, I think I have a worthwhile point to offer:

Let's not forget, Goldman Sachs and its biotech brethren are businesses. All business involves long-term strategic planning, often behind closed doors, to answer the question of "what application of our existing money will make us the most money in the future?" When viewed through this lens, Goldman's statement can be polished up to "of all the biotech investment options we're weighing, investment in outright cures for infectious diseases is less profitable in the long-term because curing people has a nonlinear effect on the patient population." It's a simple statement of fact.

OP's summary, and I strongly encourage you to actually read it if you haven't, goes on to say that Goldman's research suggests long-term research and product investment would be best applied to medical conditions like cancer and aging, for which a cure for an individual doesn't result in a diminishing market.

This isn't nearly as evil-sounding as the article aims to make it sound. At worst, it highlights something we already know: market-based solutions tend to be flawed, and if we want investment in treatments for infectious diseases we need to turn to forces that are exempt from market forces (i.e. government research funding). At best, it's an indication that we can expect more investment to go into things like cancer and age-related diseases.