We don't worry too much about killing an ant colony. Which always feels like it should be different when "sentient" beings are involved, but humans are so limited that beyond 150 people we struggle to conceptualize of other sentient minds as "real".
So really it could go either way: alien intelligence so advanced and vast that we don't seem meaningfully alive to it, or alien intelligence so advanced and vast that man's inhumanity to man makes us seem impossibly savage and dangerous.
I think it's a mistake to assume that aliens will be overly similar in their thought process.