Focal length does not mean the lens itself must be that long. It is the optical distance from the lens’s principal plane to the image plane when focused at infinity.

On a large-format camera, much of that distance is provided by the camera bellows, so the lens does not need a long barrel or built-in focusing mechanism. Large-format lenses are often just compact optical cells on a shutter board, with focus, tilt, and shift handled by the camera body.

By contrast, many 35mm lenses include their own focusing helicoid, and SLR/DSLR lenses may need more complex optical designs to work around flange distance and other constraints. Zooms are especially poor size comparisons because they require many more elements and moving groups.

Also, “telephoto” in the strict optical sense means a lens designed to be physically shorter than its focal length, which usually needs extra optical complexity. View cameras usually don’t need that because the bellows can extend to whatever distance is required.

So large-format lenses often seem shorter because the camera supplies the extension and movements, allowing the lens design itself to stay relatively simple and compact.