I mean, the term refers to portrayal, no?
lol No, it's both. you can't cherry pick one side that supports your claim (even thou it doesn't) and not the other half. For example: by portrayal he failed with preventing a massacre and containing sasuke from corruption. unlike for example, minato who not only protected his village with barely any deaths involved but instilled a ridiculous foolproof plan to get naruto all the keys to becoming stronger and somehow went perfect without the need to speak to anyone other than naruto one time subconciously all the while he's dead unlike itachi who realistically had to physically live to intervene in events to make sure it goes smoothly. So idk whose the idiot that keeps spreading that nonsense that itachi was protrayed flawless stu thou I do have an idea who the moron could be.
portrayal applies to strength as well, itachi obviously needed to be edo form in order to defeat kabuto, that's a crutch, not a character strength. his genjutsu solos is justified because genjutsu in general always solos and even during times that it didn't it very easily could had if plot weren't in the way. example: what if plot didn't have sasuke join itachi against kabuto? itachi would've remained in the genjutsu. what if plot didn't have sasuke try to stab danzo but instead use amaterasu immediately after catching danzo in genjutsu? GG. Could do this all day but that's enough. No one in this series is a Stu and if there is then Minato and transmigrant characters are more likely cannidates, especially naruto because he wasn't loser unlike rocklee but rather a late bloomer prodigy and his deception skills is arguably equal with itachi's and sasuke's maybe even better since he does't have to mask it under invisible illusion trance and somehow finds a way to persuade almost every villain to be good and join his cause even better and easier than luffy from op