>>714773489
when you're a little kid watching, she's "just like my bratty little sister" so you naturally dislike her. Watching as an adult you become aware of the fact she's spent a long time constantly fleeing for her life from people trying to kill her, and basically the entire fate of her timeline is resting on her shoulders. Constant soul-crushing stress fear and worry she has to put aside and focus on the mission at hand (despite being about 7). So of course she has zero tolerance for Usagi's foolishness.
Even after the future is saved and Usagi learns who she is, she still never tries to act like a mother figure to her, instead picking fights with a little kid as if she is one herself.