>>55840141In order to give you a serious answer while the thread's still early, it's because the story was "too real" for the anime to adapt.
Take away all the whimsy and fantastic elements from the Pokemon and Lusamine's story is ultimately about a grieving widow, broken by the loss of her husband, turning to some form of substance abuse (pursuing Ultra Beasts by any means necessary and eventually getting doped up on Nihilego toxins) to cope and subsequently losing sight of who she once was (going from someone who cares for animals to abusing them for her fix) and becoming excessively abusive towards her children due to her fractured psyche, and it's only when her daughter finally finds the guidance to confront her about it in an intervention that she's finally snapped back into reality from her overdosing to realize the kind of monster she's become and how much it's hurt her children, her sole remaining links to her husband.
The anime can't fucking adapt a story like that when it's aimed at toddlers. So naturally TPC and OLM flipped their shit until GameFreak rewrote her significantly into a dindu nuffin who always had good intentions in mind and simply did an oopsie daisy in handling Nebby and was never abusive at any point, and then the anime dumbed it down even FURTHER just to be safe.
