Have you watched any old trailers recently? They're weirder than you remember. Instead of allowing edited clips from the movie to encapsulate the film's story succinctly, older trailers used voice-over artists to literally tell you the story.
"In a world where…" and "(Insert plucky protagonist here) was just your average joe until (insert major plot point here) took them on the journey of a lifetime" were common phrases uttered over the top of virtually every trailer. Nowadays, we just get ominous horns and drums that steadily ramp up through the trailer as clips from the movie shuffle like Blackjack dealer on coke.
Every once in a while, I like to wonder what older trailers would look like in the modern style of movie marketing. In the video linked above, the YouTube channel Floris De Canne made a modern version of the trailer for Star Wars Episode V: The Empire Strikes Back.