'Julius Caesar' by Shakespeare isn't about Brutus after Caesar dies: it's about Mark Antony

Everyone says it's about Brutus because of all the stuff that happens to him and that he does, but are we forgetting Mark Antony goes ballistic and:

-Pretends to be friends with the conspirators
-Manipulates the Roman public to listen to him (Friends, Romans, countrymen, lend me your ears)
-Incites a riot through his manipulation (Friends, Romans, countrymen, lend me your ears)
-Forms a Second Triumvirate with Octavian(Augustus) Caesar and Lepidus
-Fights and wins a civil war against Brutus and the conspiritors
And all in the span of a year(in the play it's all in 44 BC, despite the facts of history saying otherwise)