It's quite clear that her departure has been planned since before any of the wizard game drama happening and people pointing to that are just trying to feed into the narrative that she was bullied off the internet when this has been a decent time coming. It's timing pretty well with the end of the Japanese fiscal year so she's probably not renewing her contract. They've also planned a popup store around her graduation so they've had to have known since before the wizard game shit. There's probably something behind the scenes that is influencing the decision and she might just be going independent or joining another group entirely.