This is why Hollywood never seems to learn the correct lesson. After reasonably original movies like The Avengers, Deadpool, or Mad Max: Fury Road turn into “surprise” successes, the suits believe they should make more movies about superhero teams, swearing superheroes, or postapocalyptic destruction derbies. First of all, there’s nothing surprising about a well-made story being a success no matter how little it has in common objectively with any prior successful work — (un)familiarity doesn’t make a story good, or bad. It just makes it (un)familiar, which can at most be a marketing issue.
My husband and I had almost this exact conversation walking out of Deadpool.