Hard disagree about declarative "X is Y". It's a failure of weakening attention span. There are plenty of excellent long movies:

- Once Upon a Time in America (1984) 3:49

- Lawrence of Arabia (1962) 3:47

- The Irishman (2019) 3:29

- Malcolm X (1992) 3:22

- The Godfather Part II (1974) 3:22

- The Lord of the Rings: The Return of the King (2003) 3:21

- Schindler's List (1992) 3:15

- Gandhi (1982) 3:11

- The Green Mile (1999) 3:09

- The Deer Hunter (1978) 3:03

- The Lord of the Rings: The Two Towers (2002) 2:59

- The Lord of the Rings: The Fellowship of the Ring (2001) 2:58

- Casino (1995) 2:58

- Braveheart (1995) 2:58

- The Godfather (1972) 2:55

- Django Unchained (2012) 2:45

What I most object to is lazy storytelling for lazy, second-screen audiences lacking in style and subtlety having a robotic, spoon-fed, infantile, unnatural, expository narration quality in every character like it's a commercial for an antacid.