I think there are two distinct camps. People who experienced the ride before and people who experienced the ride solely after. Neither likes the other version...
Like learning that the previous version of small world was a narrative of world war. I love new Sindbad, the old version not so much.
Hmm, not exactly the same thing. The tales of Sindbad are akin to fairy tales and are well-known (as witnessed by the numerous movie adaptations thru the decades). It is decidedly
not about an Arabian singer traversing the world, making music with strange creatures and an adorable tiger.
Small World, on the other hand, was developed specifically with a singular message of international unity; in fact, it's right there in the name!
Still, I get what you're saying as far as Disney experiences go. Perhaps it's more akin to the differences between Phantom Manor in Paris and the Haunted Mansions in the states. One is a tragic tale of horror, the other is a light (if macabre) fantasy about ghosts. I can see how people who liked one of them would not appreciate their ride being transformed into the other...
Still, there was nothing else in the world like the old Sindbad.
It was truly a one-of-a-kind attraction. It's unlikely we will ever see its ilk again. I'm lucky I was able to experience it when I did...
[Incidentally, here's a fascinating bit of history: Disney stalwart Ub Iwerks independently produced a Sinbad the Sailor animated short in 1935.
It's available to view on Wikipedia, for those interested:
https://en.wikipedia.org/wiki/File:SinbadTheSailor.ogv ]