The park has to change stuff to stay relevant, as well as to milk those properties (like Star Wars) that they've poured billions into. This ride was based on an old, practically unknown movie, and it was just a matter of time until it got a major overhaul.

I still remember when Pirates of the Caribbean spawned a movie, rather than vice versa, when the Troll Ride existed at Epcot, and that goofy World of Tomorrow show they used to have. But stuff changes, and will continue to change. Even at Disneyland, as compact as it is compared to Orlando, they've got a lot of real estate that could generate a lot more money. I'd expect stuff like Tom Sawyer or that train ride through the Old West to give way to more attractions tied to modern movie franchises.