The parametric constraints should work in Perspective View but only if the objects and dimensions are 2D and on the same plane.
I drew this rectangle and then dimensioned it in Screen Plane and then put both items on a 3D plane using the OIP.
When the rectangle is altered the dimension updates.
3D associative dimensions have been on the wish list for a few years now but alas it is not deemed important enough to instigate, which is odd as the world seems to be using, or at least moving towards a complete 3D workflow.