- 'Reliably'? Outside of one outlier year, how many of these movies actually returned a billion at the box office? It's certainly fair to call a movie a flop if it doesn't even make back its budget, but anybody who thought it was reasonable to expect Marvel to keep hitting homeruns every time at bat is fucked in the head. Between Phase 4 and Phase 5, Love and Thunder and Quantumania were the only legitimate outs, no matter what the box office says. Eight out of ten movies have been, at worst, base hits, which hardly seems like a reason for doom-casting to me.
To me, I said "reliably" because that's been the case. That doesn't mean every superhero movie was going to do Billion+ but more likely than not, there was a reasonable expectation (depending on the title/critical response) that most superhero movies - primarily MCU I'll grant you - would at least get close to $1 Billion if not top it. When I say close I also meant $700-$800 Million numbers.
There've been 50 movies that have hit $1 Billion worldwide, here the superhero movies are in release date order then box office low to high if they share the same year. I don't believe these are adjusted for inflation either. There are 14 with TDK just barely missing.
Just Missed 2008: The Dark Knight made $998.725 Million. This was one of the first superhero movies to make people think $1 Billion wasn't out of reach for the genre. Worth noting this was just 8 years after X-Men was released to just under $300 Million worldwide and 5 years after X2 topped $400 Million worldwide.
2012: The Dark Knight Rises
2012: The Avengers
2013: Iron Man 3
2015: Avengers: Age of Ultron
2016: Captain America: Civil War
2018: Aquaman
2018: Incredibles 2
2018: Black Panther
2018: Avengers: Infinity War
2019: Joker
2019: Captain Marvel
2019: Spider-Man: Far From Home
2019: Avengers: Endgame
2021: Spider-Man: No Way Home
Other notable numbers: Doctor Strange in the Multi-Verse of Madness made $952 Million; 2007's Spider-Man 3 made almost $900 Million (about $5 Million short); Spider-Man: Homecoming & Batman v Superman: Dawn of Justice & Venom all made between $850-$870 Millon. Those are relatively huge numbers.
Of the 99 movies to ever gross over $800 Million worldwide, just 5 were released before 2001. I don't think it's far-fetched to say that the success of the "prime" MCU and Pixar's emergence changed the landscape of what a movie really could accomplish. Then you throw in IP (Harry Potter, Lord of the Rings, Star Wars) and Disney in general... expectations rightly? skyrocketed to what could be.
I don't think there should be doom casting/pessimism at superhero movies but it's a fact that if they are being thrown out at $200-$250 Million a pop and see 2-4 different properties released throughout a year... there is either going to be fatigue or they
have to hit home runs. Getting singles and doubles isn't going to cut it when you've had Deadpool and 2012's The Amazing Spider-Man making over $750 Million worldwide. Even 2016's Suicide Squad made $745.7 MILLION and most critics/audiences didn't like that movie! You see numbers like that and you reasonably think to yourself, "Yeah, maybe Morbius isn't great but it could still make $400 Million," or you look at Quantumania and go, "The sequel made over $600 Million. This is the 3rd, we have this big budget used for it. I can't foresee it making under $550 Million in a worst-case scenario."