Making movies is hard, I understand that. A lot of blood, sweat, and tears go into making movies.
With that said, it literally should not be this hard to make a D.C. Cinematic Universe. It's not like the concept is unprecedented. There's over 70 years of comic history over thousands upon thousands of comic book pages, to draw inspiration from.
The fact that Warner Bros and D.C. are dropping the ball so hard is mind boggling, especially when their animated shows like Justice League, and their animated films (with the exception of The Killing Joke), are really good.