The funny thing is that Star Finger only appears once in the entire Jojo franchise. It is quite frankly a deus ex machina mechanism what gets Jotaro Kujo, the protagonist of part 3, out of an otherwise unwinnable fight, and then is promptly forgotten. The ability to extend your stands index and middle fingers, and only those fingers as far as it is known, is rather bizarre, even for JJBA standards. In part 3, when Star Finger is introduced Jotaro’s stand is nothing more then a punch ghost, still expanding its abilities. Introducing such a move would be expected to hint at potential further development of Jotaro’s abilities and fighting style, but instead the audience is delivered a one time red herring dipped in spicy funky sauce. For all its strangeness, Jojo’s Bizarre Adventure rarely has such one off abilities or deus ex machinas, especially after part 1, making Star Finger particularly bizarre even by the series standards.
Therefore it is no wonder that Star Finger is one of the most brought up instances of the phenomenon “Araki forgot”.