>>149857530 (OP)
>Why was The Marvels the first MCU bomb?
Carol's first movie benefited from being sandwiched in-between Infinity War/Endgame and peak MCU popular. Her sequel benefited from none of that, it had two co-stars from ill-advised Disney+ shows tacked onto the movie, and it had a slew of other problems leading to a box office disaster of epic and based proportions.
>Why was The Marvels the only MCU flop?
Huh, Eternals and Thunderbolts* a.k.a. New Avengers didn't exactly light up the box office the same way as Avengers: Civil War, Avengers: Infinity War/Endgame, Black Panther, Deadpool & Wolverine, and the MCU Spider-Man movies did.
Also, Captain America: Brave New World underperformed compared to Civil War and Winter Soldier. And while The Fantastic Four: First Steps will outgrossed prior FF movies, Marvel's not quite happy with its box office run, especially compared to DCU's Superman.