I'm super late to the party on this, but I agree with Scorsese about most superhero films being amusement park rides that have prevented more mature films from gaining the limelight.
Filmmakers within the superhero genre have been able to insert adult ideas into them (Both "Wonder Woman" films, "Black Panther" to name some), and those filmmakers are talented people who deserve the praise or criticism for their hard work just as other directors do.
I think the genre is a great platform to launch new and exciting talent with films that people are guaranteed to see (at this point anyway). However, we shouldn't leave the older generation of directors specializing in character dramas set in the real world down either.
Directors like Scorsese inspired some the people making superhero movies to become directors in the first place ("Joker" Would Not Exist without "Taxi Driver" or "The King of Comedy"). They changed cinema forever, and their contributions should never be forgotten.