Because someone challenges your pet idea about cosmic rays, you don’t get him anymore.?!
Job is interesting, but hardly conclusive scientific evidence, which is what we are talking about here.
Yes, parasites kill for food, and so do humans. Humans harvest all sorts of plants and animals for food, and yet we have a symbiotic relationship with them, as do most prey and predators.
Competition between prey and predators is not for scare resources, because lions cannot eat the grass that zebras eat, nor do zebras eat the zebras or other prey lions eat. They need each other, which is what symbiosis is about, and conflict is not.
That is the way God ordered the Creation so all things work together in harmony, which some occasional exceptions that prove the rule. I think that is what YHWH was saying in Job. YHWH ordered the universe, so YHWH does not need to micromanage it.