Well, before this whole thing came out (pun unintended), Vito was Phil’s go-to guy/mole in Jersey, and fed him the ideas of grandeur in order to cause a bit of friction within the famiily, so it’s really just homophobia/family “honor” that drove him to kill Vito.
Maybe not … what if Johny Cakes reads about it in the paper and gets all sentimental. He recruits his guy fireman buddies and they all go down and turn the NY/NJ mob families updside down making the world safe again. It could happen!