Kuro will go out of its way to gimp characters when they are not played in their BiS teams.

Zani Frazzle application, Carte Erosion application (+HP scaling to fuck over SK), Lupa requiring 2 Fusion teammates (when there is only one Fusion healer in the game). And next patch is Phrolova who NEEDS Cantarella...

They can't lower the currency income, or release more than 2 characters per patch. Weapons are also guaranteed. So the only way for them to milk players is to "encourage" them to get characters they don't want with a risk of losing 50/50 and spending more.

Like all gacha companies, they are a gacha first, game second company.