You shouldn't have to "do research" to enjoy a theme park ride.
Face it. The original "El Rio" was a weak attempt to create a ride in World Showcase (and, at the time, the only "ride" in WS after the German ride got axed)
It was born out of the idea to build a Florida version of Disneyland's "Blue Bayou" restaurant, but without a show like DL's "Pirates".
To those who think Disney is all about storytelling, "El Rio" had no story.
To those who say the original EPCOT was about education, name two things that you learned from "El Rio".
To those that complain that the parks are becoming too "Pixar-ized"--- The Three Caballeros are a 63-year-old Walt-created original that I'm sure did not get dreamed up by the merchandise folks. This appears to be a genuine attempt to pay homage to a vintage Disney film in a setting that is most appropriate.
The original EPCOT failed because it did not appeal to a wide audience. Sure, sophisticated adults may have flocked to the place. But parents with children avoided it, simply because it was "boring".
Now with Nemo, The Three Caballeros, and characters galore, younger tastes have something to enjoy as their big brothers and sisters race off to the thrill rides, and their parents soak up the ambiance of international locales.
Now, everybody in the family can find something to enjoy. That enjoyment means they spend more $$$. More spending means continued investment in the parks. Everybody wins.