Not really. The humans do bad things because every other option is worse. Humans kill aliens because most of the aliens make xenomorphs look harmless and friendly and the rest make mind-raping body-snatchers look like good allies. The only way to argue the humans deserve to be attacked or destroyed is to ignore the entirety of the Imperium's reasons for xenophobia. And also to ignore the alien protectorates the Imperium has (peaceful aliens). The purgation stuff is more "kill the bad aliens" and normal policy is to focus on regulating the "friendly" aliens to prevent scarcity from causing wars and to organize them against mutual threats beside the Imperium in local defenses. Even if it wasn't, again, the only way to think the humans in the setting are "bad" or deserve or need to be destroyed is to ignore the aliens' evil and to pretend that the humans should prefer to sit back and be annihilated, enslaved, eaten, soul-devoured, soul-raped, mind-raped, actual-raped, whatever-ized by xenos because fighting back is "bad" because the poor widdle xenos would be hurt.