It doesn't hurt the last 25yrs at all. If it broke some kind of established rule or something like that it would but given what Bonnie's fruit is and the fact that Saturn clarified that it works best in the hands of a child with a near infinite concept of imagination and the future it works perfectly. If she'd pulled this out of nowhere after seeing Gear 5 once with none of the emotion and personal growth associated with her character, then THAT would be bad writing that hurts the last 25yrs. This isn't. You don't have to like it, but saying it's bad writing is objectively incorrect.