These devices are relatively easy to put on sites, and if used tastefully, add to the interest and attraction. The content, look, design, and colors of a site can be changed at will. Obviously not so in other media. It's true that many of the elements of a web site can be found in other media. Film and television have color and motion, but at greater cost.
Newspapers change content daily, but a web site can change content in real time.
The amount of text and illustration is limited by the format of other media, but the only limit in a web site is the ability to sustain attention and interest. Perhaps the most important difference, and the one that should most affect the site's design, is that a web site is dynamic, and the printed page is not. Just the ability to link to other pages makes a site a significantly different medium. The printed document may describe a firm and its practice, but it's a static description. Pages are generally turned sequentially, like a book.