I agree with this in spirit, but I do worry - is maybe the reason they don’t allow parser plugins that it could be a security nightmare and or lead to super buggy / unpredictable results?
I know that when I was fiddling around with parsedown (a PHP Markdown parser) I did an extension of my own to plug in a couple features and I had to fight with it a bit to avoid causing really ugly downstream issues that tripped up the functionality - It turned out most of the issues were between the chair and keyboard, but It was monumentally easy for me to do dumb things and I wonder if the amount of effort to properly sandbox such a parser plugin architecure might be a bit high?
Honestly though yes I would love this - my first thought when reading through the request and the followups was “how come there haven’t been like 100 folks writing plugins that address this”