Adding to Marvel’s pains for the upcoming Avengers sequels is the fact that they dropped the actor playing their next big bad Avengers villain, Kang the Conqueror. After Jonathan Majors was convicted of assault and harassment, Marvel dropped him and, presumably, the Kang storyline with him. If the Russo Brothers sign on, they don’t currently have a big bad like Thanos that has been built up as a threat in previous projects.
Of course, Marvel will undoubtedly change that and introduce the replacement villain (or replacement actor if the Kang storyline does continue) before the Avengers sequels. Originally, the title of the fifth Avengers movie was Avengers: The Kang Dynasty, but it reportedly will be getting a new name. So, the Russo Brothers should have some creative wiggle room if they do sign on.