Just as the original Iron Man movie was the first planned by Marvel Entertainment (and was a contributing factor in Disney buying the company a year after its release) launching the Marvel Cinematic Universe, Man of Steel was settled upon by DC and Warner Bros as the initial film to introduce/re-introduce their characters in an unstructured fashion--primarily in response to the former's success with its Phase One that ended with the first Avengers film. Like Tim Burton, Christopher Nolan created his version of Batman purposefully as independent and separate from any long-term plan (organized or just thrown together) between a publisher and a studio.
I agree about The Dark Knight. However, I do give Zack Snyder props for his director's cut of Justice League. Warner Bros' handling of that film (allowing Joss Whedon to gut and re-shoot it) is a prime example of the studio's lack of vision and bungling of its own DC Extended Universe.