Making Sculpt Brush Textures Displace Along 3 Axes

Hi, currently Brush Texture nodes don’t seem to map / use RGB to displace along XYZ in Sculpt Mode which is something I’d like to see changed. To verify you can hook up a greyscale / single channel via a combine RGBA node. Like so:
The displacement is always along the Normal or Z or Height (of the Area Plane, View Plane, etc) no matter the input socket used.

Currently I’m grepping around in the source for pertinent code / keywords that may rectify this.
If anyone has any insights / inklings there and time to share them it would be appreciated.

Eventually supporting tangent space VDMs in Sculpt Mode would be something of a standard to work towards.