Think about it. The first episode, the FIRST EPISODE, they had a person whose entire compound and people getting killed by the Covenant right infront of his face in 4-Fucking-K... immediately believed tried to kill Master Chief because he saw him and the other SPARTANs coming and thought they was going to kill them.
Then when the UNSC tries to get the girl to tell them that yes, The Covenant exists and to tell people about her experiences to get people to prepare for war, she IMMEDIATELY blows them off and goes into some stupid ass rant about how much she hates the UNSC despite she literally saw The Covenant slaughter everyone including her dad minutes ago.
Combined with this, it feels extremely apparent that they are trying to act like the genocidal, planet glassing Covenant are somehow the lesser evil compared to the UNSC and that's the most assbackwards thing I have ever heard.