The legacy of the films—technical achievements, continuity and coherence of narrative, ambition, etc.—are laudatory in some respects. Obviously, they made an enormous amount of money. But it's worth examining their "critical" success. Putting my personal opinions aside, do any of these films hold up to the standard bearers of early 90s and 00s blockbusters? I'm not convinced.
The MCU films are inherently derivative works with little dramatic tension; we already know the characters and that they will win. The narrative and dialogue is paint-by-numbers, and the action sequences are exhausting, low-stakes, and sterile.
That's fine for a theme park ride—get some thrills if that's your cup of tea—but it's not enough for a critically good blockbuster film. That's fine for teen boys and young adults, but it's not enough for a more diverse, discerning audience. Does anyone think any of these films, let alone their entirety, hold a candle to Jurassic Park, The Matrix, or The Pirates of the Caribbean? They're equally blockbusters, but they will be remembered long after the MCU films are forgotten.