While something like this can be done with grouped objects in Inkscape and going into object dialog, I think this feature could serve as a great use for artists to use to avoid going outside bounds of drawn area. To clarify upon this, let's say I want to make a car render in Inkscape. If I have to do that, then the first thing I need to do is to define the shape of the car in separate pieces. Let's go with the outerbody. For me to start with there, I need to make a grouped object and set clip, and then I work within the grouped object to avoid going out of bound of the expected drawing area.
This also would make it easier to make fog like effects.
Also, it would be a bonus if you can make a layer chained to the clipping mask. To clarify, let's look at photoshop. You can set up an alpha mask next to a image, and it can be chained or unchain. Chain means that whenever you move a object within photoshop, the chained alpha mask also moved.
This should be seen within the object dialog, and layer dialog. Preferably the object dialog since it's kind of a better layers in some way, but I'm aware they're not the same.
Similar to this, maybe: https:/
(but the extension uses filters to achieve the result)