Other life forms on Earth pose no threat of dethroning humanity. Even the ones that were major thorns in our side, we exterminated or nearly did.

If there were life forms on Earth that posed a threat of dethroning humanity in the future, which we could relatively-painlessly exterminate now, and which had likely-irreconcilable goals with ours, yes, I'd advocate genocide.

>Why do you think that all civilizational advancements so far were built on extending cooperation and consideration?

They weren't. The last 80 years have seen a fairly-drastic expansion of circles of concern, but if you go back further it's not monotonic, it may not continue in the future, and it's most certainly not the foundation of "all civilisational advancements" unless you define the latter in such a way as to make the statement a tautology.