I always wondered why people thought Kalros taking down the Reaper was a good thing. She's organic, and her body is in complete contact with the Reaper... and dying isn't enough to stop a Reaper from indoctrinating or making husks. At the very best, there's now a Reaper corpse underground indoctrinating people that don't know about it. At the worst, a significant portion of it merges with one of the largest life forms on the planet.