It's the silliness of the contrast between them. Similar to the animal crossing and doom communities coming together and creating memes when their games launched on the same day.

They just happen to be the two biggest movie releases of the year this far. I think they beat all the Marvel movies and the new Indiana Jones in box office, which signals that serialized movies are not the huge phenomenon they used to be just a few years ago. They are also received very favorable reviews. So they are just getting a lot of positive attention.

It essentially started as a meme