I wonder how pandoc[1] does this. You can convert Markdown to PDF (`pandoc test.md -o test.pdf`), it uses the same syntax as GitHub ($ signs only, no backticks) and it fares a lot better than GitHub in a few of the tests outlined in the article[2]. It's not perfect but clearly something better can be done.
[1]: https://pandoc.org/
[2]: https://nsood.in/hn-latex/test.pdf