So what justification do the pokemon in pic related have for being ghost type? I was always under the impression, prior to gen 7, that ghosts were spectre like and intangible, but then they retconed them to just "creatures with spiritual powers". Can you honestly imagine for instance a machamp punching a decidueye and its fist just passing through it like it would with gengar or dusknoir?
Before gen 7 i'd give frillish and jellicent the benefit of the doubt but they're just regular animals. Even their creator disagreed on the ghost type and said had they come out a gen later, they would've been water/fairy.
I also considered putting trannypult on this list but dreepy's dex say it was reborn as a ghost, whatever that means