Anime

I think it's just a matter of telling the consumer that this is the slop they want as quickly as possible. That's why the stories and settings themselves have been in a race to the bottom to be instant-gratification power fantasies (sexual or martial), probably most obviously with the gamification of settings with literal in-universe menus describing everything in terms of stats in a way that would make Akira Toriyama blush. Actual story beyond power fantasies is withering away, a process hastened by constant pruning.

I do think long titles can be fun. The first example I always think of is: The Pilgrim's Progress From This World to That Which Is to Come: Delivered under the Similitude of a Dream Wherein is Discovered, The Manner of His Setting Out, His Dangerous Journey; and Safe Arrival at the Desired Countrey. It's quite a lot like what you describe, since it doesn't just give the premise but explicitly summarizes the plot.