This is a surprisingly long trailer, filled with detail. I can guess why Apple did this.
Some (if not most) Apple Arcade games have relatively simple stories to tell. Frogger is a well known game mechanic. Stay alive, pick up stuff. Gorgeous, but relatively simple.
Same with many other Apple Arcade games. Oceanhorn 2 is a much bigger game, with more game mechanics to master and a much larger story to tell. It’s beautifully built, well balanced, and a lot of fun. The trailer does it justice.
On my short list of best Apple Arcade games.