Marvel has seen an unprecedented amount of success since 2009's Iron Man, starring Robert Downey Jr. Fans anxiously awaited each entry into the franchise after that, and who could blame them when Samuel L. Jackson specifically name-dropped The Avengers? That success continued all the way up to 2019 when Avengers: Endgame went to theaters, showing the world how to properly culminate a 21-movie storyline. However, popularity afterwards gradually dropped off.