I tend to agree with simzy on this one.
My impression has always been that MAME tends to go out of its way to preserve hardware bugs. I would argue that given the LCD/VFD being such a critical component of these games - they're not like arcade machines where you can hook them up to any monitor - accurately preserving printing errors and the like is important.
With part of the value of MAME being in its dispassionate documentation of history, a manufacturing defect is practically the textbook definition of the sort of thing that it should preserve. Games didn't exist in a vacuum, poor manufacturing tolerances or standards is an important thing not to varnish over.
If these printing/manufacturing defects are so relatively few and far between, how much additional workload would it be to provide a "fixed" set of artwork as a separate artwork file, while keeping the SVG within the ROMset itself as accurate as possible to the source material?
There's always going to be some level of variation, as the SVG is being done by a human manually tracing over photos, and this is exacerbated when it comes to VFD games due to the grating that sits between the segments and the camera. But in my belief, things like asymmetry, or visually bridged segments, should be the presentation given to users so as to preserve an accurate first impression of a title.