>>30931433/vp/ hates her because she's a know-it-all, who acts very obnoxiously towards any character that isn't you and basically fucks over the earth at one point. Plus there's this mis-information that she told Archie/Maxie about Groudon and Kyogre, basically dooming the world in order to save it.
Reddit likes her because she's a know-it-all, but she's implied to be a death seeker over the loss of her loved one (child/previous lorekeeper). Plus they know she just joined in on Aqua/Magma's lower ranks, as opposed to telling them all about Kyogre/Groudon.
Tumblr likes her because they think she's a lesbano who has a crush on the female player character.