Is this intended for VR games only, or for general games?
i don't think i quite understand what exactly you mean. making grafitti in VR is generally harder than on a simple drawing tablet and these kinds of physics sims are already used for litter placement.
The only reason I can see to use a VR interface for gamedev would be for placement of objects, since that can save small amounts of time.
creating dirt textures and such is still a thing because calculating the complex physics of how dirt crumbles and behaves on a small level is super compute intensive, and certainly wouldn't run in realtime, even less so when doing that in VR.
maybe i am missing ur point completely though.