As a mathematician editor of Wikipedia, all of my file uploads are diagrams I have created using LaTeX. Although now I upload them as SVG files, which are at least editable, there is no real indication of the logical structure of the image, only its elements (however logically described as images). I think it would be a useful service to allow somehow attaching the source LaTeX file (or files) to the image so that it could actually be edited by someone else, rather than laboriously and imprecisely recreated.
One technique is simply to rename the LaTeX source with an acceptable image file suffix (i.e. file.tex -> file.svg but is still a TeX file) and upload it alongside with the image, but this is confusing both to editors and the software, if it is even possible (I haven't tried). Also, it is impossible to indicate the association between versions of the source code and versions of the final image, which would be useful for exactly the same reason revision histories are useful in articles.