>"because only humans have the insatiable appetite for destroying each other."

Chimpanzees 'go to war', and so do some non-great ape species like ants and termites. Interestingly, some ant species conquer other colonies and essentially 'enslave' the defeated worker ants using pheromones. It stands to reason that belligerence would arise elsewhere in the universe because it has on Earth several times.

https://en.wikipedia.org/wiki/Gombe_Chimpanzee_War

Any life on Earth basically is and behaves the same. We're all cousins here.

It is unreasonable to assume aliens are anything like us.

When you're sample size is 1 it's wrong to assume that the general population is exactly like your sample. Of course, it's slightly more wrong to assume the general population is nothing like your sample.

It's entirely reasonable to assume that any life that evolves under resource constraints will have violent competition somewhere in whatever means of intergenerational data transport they use.

Unless we are some true outliers, like way the hell off the farm, we are likely to share with them some basics in terms of continuing to exist amidst neighbors and ignorance.