>>33471271Gamefreak is not a savaant on its own game mechanics, and they also aren't the most efficient coders, or weren't for a long time, at least. They're slow as a fucking snail actually, and they have trouble identifying problems or outdated stuff that's wrong within their own ever-expanding amount of items/abilities/moves, reason why they take so long to fix shit that should be obvious.
Even if things like electric types being immune to paralysis and curse being a ghost type move are things that come off as obvious for anybody on hindsight, truth is that the way these mechanics were originally different from the way they "should be" is always a matter of context (I bet at the time no-one actually cared/had enough foresight about what type curse should be), resources (coding a move that has different effects depending on type was probably hard enough for them as it is, and I would bet things like flying press or sucker punch would have been impossible for gen 1-2 gamefreak, or at the very least glitchy as fuck) and concept (maybe the intern that came up with curse thought being a ??? type move would be unique and cool with the kids).
The pace they take for this kind of stuff is abyssmal. To put you in perspective, it is likely that at least 1 /vp/oreon will die of age before they fix the hidden power formula to include fairy, or make silvally's RKS system include z-crystals.
TL;DR - Gamefreak are slow and don't know what they're doing most of the time except when they are, which is not too often.