While I agree with you about the attraction, society has changed and with it, the attractions need to change or you risk having a huge attraction with empty cars going through them.
If Epcot had opened this year with the attraction lineup from 1982, it would be a flop. If DHS opened this year with the attraction lineup from 1989, it would be a flop. Why? Relevance. You need to know your audience. Epcot and MGM worked when they opened because the attractions were built with the current society in mind.
The Great Movie Ride was a history lesson... While I loved the attraction when it first opened, it quickly got stale IMO and the rest of my family never cared to ride it. Taking my family as a very small sample size (a big Disney buff that wants to hang on to any bit of Disney nostalgia in the parks he can, a wife that just enjoys going there to vacation with her children, and two young kids [9 and 5]), it's no wonder that it saw less and less riders.
You may say, "Your kids are too young to understand..." and then I'd say, "What teenager wants to ride that when Tower of Terror, Rock n Rollercoaster, a giant Video Game, and a shiny new Star Wars land" is right around the corner? Maybe the adults? Well, they're going to be steered by their children. Older folks? Again, most will be there as grandparents.
In it's current state (and even if they refurbed a few scenes), it was destined to fail going forward. To bring it back it would've needed to be a complete redo with updated tech and more relevant movies and more of a mix of classic and current. To me, the attraction dealt with the history but moreso focused on riding through different genres of films. Guess what is a HUGE genre right now? Comic Book films. Basically the only types of films keeping theaters open at the moment.