Films & TV in a "cinematic universe" are assumed to work a certain way. It is assumed that everything should be for general audiences, everything should be palatable, & nothing should be too niche or specific, but there is no rule that says because a film franchise is worth a lot of money it *must* be as generic as possible.
What are they going to do when they "have to" watch Clayface, which appears to be a legit horror movie? THAT won't be for everyone for sure.