For 4x5, this is mostly a fundamental limitation. A 4x5 frame already needs roughly a 160mm image circle just to cover the format, so a 50mm-class lens with only about a 160–166mm circle leaves very little room for rise/fall. To get much more movement, the lens would need a much larger usable image circle, which is extremely difficult for such ultra-wide rectilinear designs.

In practice, shift/rise is just using an off-center portion of the image circle. If the circle is only barely large enough for 4x5, there isn’t much movement available.

A few practical points:

• Image circle specs are often given at a certain aperture (commonly around f/16), and stopping down may give a little more usable coverage.
• Manufacturers’ image-circle ratings can be conservative, and some falloff may be acceptable depending on use.
• Center filters can help with corner light falloff, but they do not create a larger image circle.
• Rear tilt/swing are less demanding than rise/fall in terms of image circle.

So the viable alternative is usually to use a smaller film/sensor format if you need a very wide view plus substantial shift, accepting that the effective field of view changes.