Make F-Curve Modifier's Influence Animatable

Quite often I use the noise f-curve modifier to add a shake to my camera. To animate the strength of the modifier, I use an empty cube. I don't add the noise modifier to the camera, but to the cube. Secondly, I add a "Copy Rotation" object constraint to the camera, select the cube as a target and set Mix to "Add". Finally, I can animate the strength of the shake using the Influence of the Copy Rotation attribute. This is an admittedly annoying workaround for not being able to animate the influence of an f-curve modifier. But at least there is a workaround for this.

If you now want to apply a noise modifier to the focal length of the camera, this trick no longer works. This is very frustrating as this kind of shake is very interesting.

So I wonder... why not just make the influence of f-curve modifiers animatable? At least with the noise modifier, the technical effort should not be very high for that, or am I wrong?