That's just one explanation. Add the other facts like getting to an unknown galaxy, living in shitty conditions in the Nexus because of the Scourge, the munity and the exiles, pure xenophobia and the death of the leadership all at once. Heleus cluster is a complete shithole before the Hyperion arrives.
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What? Many times I forced myself not to kill because I'm playing a peaceful explorer and even so I shot the asari that was after the remtec and killed Annae after I choose to kick her from the water monopoly. The game is actually full of meaningful choices.