Although the words of the Alice text are crucial in telling the story, the visuals are just as important in conveying the strangeness, wonder, and nonsense of Alice's adventures. This is why the illustrations are so important in the book (and Lewis Carroll even references them a couple times in the text in order to explain what's going on), and also why a silent film is still able to convey the story. Actually seeing parts of the story such as the white rabbit, the disappearing Cheshire Cat, and the procession of cards is as powerful as reading about them. These parts of the story require us to mentally visualize them anyway, because they are so out of the ordinary, so being able to see them is just as effective and intriguing.
Another reason the silent film might be of interest to people today is that it shows how people interpreted Alice's Adventures in Wonderland closer to the time it was written. Seeing what parts they included and what parts they left out made it interesting to me, as well as seeing how they interpreted it when restricted to mostly visuals.
