system
Given the following post, respond as if you're commenting on Reddit:
human
[A Quiet Place] What evolutionary purpose would it serve the aliens to kill everything?

It seems like the aliens in that film would immediately kill almost anything that remotely made a sound. 

From an evolutionary stand-point it seems like that species would wipe-out almost all its food sources in a short while. Not to mention literally blindly jumping out at any noise is not a smart move either.
gpt
We're seeing a single species (or group of closely-related species) pulled out of their native ecosystems.  Just like studies of animals in captivity, their behavior may not be at all indicative of how they acted in the wild on their home planet.  

They may be chronically malnourished due to nutritional incompatability with life on Earth so they desperately attack any sound out of hunger.  They may be nesting and are territorial to protect their growing broods.  They might just be crazy from some element in the atmosphere that keeps them in a constant state of irritation.