While I think vector painting is out of scope for something like Krita, vectors as a aid for raster graphic applications is not out of scope. I sometime use alpha threshold(color adjustment - alpha) and with vector layer on separate layers to try to mimic aliased vector layer. Useful for creating alpha on old game mods. Does anyone else can benefit from this?
It could be made into a property of the vector layer – Qt allows disabling antialiasing in QPainter, which is what we use for vectors layers. I’m not sure I would feel much urgency to look into it, though 