I'm going off of vibes more than concrete examples for this one... but... I was rewatching "The Incredibles" (2004) while working on something and I really appreciated that the movie didn't feel a need to... stop and explain the basic concepts of superpowers, superheroes, or any of the golden-age / silver-age superhero action tropes that the film is playing with.
Like, I would say that the film is both in direct conversation with classic superhero media and stands alone well. The movie DOES serve as a perfectly fine introduction to its genre, because it's a well-written movie that introduces all of its worldbuilding elements pretty clearly, but it also... it both moves pretty fast, operating under the assumption that you are roughly familiar with superhero media already, and doesn't seem to feel the need to justify itself.
People have flashy powers and improbable secret identities and silly costumes and superspy technology, and it's just... there. That's how this world works. It doesn't matter how Mr. Incredible or Elastigirl developed powers or started fighting crime or built relationships within the community, because that's not what the movie is about; that's the starting line. While the movie pokes fun at many of its own spec fic elements, it also hits the ground running, trusting the audience to catch up to "this is an established superhero" as it establishes the film's relevant problems.
I don't know, I feel like I've watched more than a few live-action superhero movies that I'd describe as "scared of their own basic concepts" and treat the audience as incapable of easily digesting the idea of some guy having superpowers or fighting big scary guys, as though that's not one of the oldest concepts on the clay tablets or in oral storytelling traditions. And so these films VERY slowly handhold the audience through an origin story. I'm bored of that; especially since it's been 22 YEARS since "The Incredibles" kicked off in medias res, followed by non-stop superhero movies every damn year.
Maybe this is a criticism that I'd extend to speculative fiction generally, including fantasy. Like, it's a damn dragon. It exists in this world. We get it. Everyone knows what a dragon is and it's really not hard for the toddlers to get it too. Tell the actual STORY now, please. "Once upon a time, there was a dragon," is not by itself a good story.