The Julia language is a fairly regular topic on this site.
Here are some of the stories this year that would qualify for this tag.
Perhaps a meta tag would solve this once for all? lang:$whatever so one could blacklist or whitelist all or some languages?
What’s the problem with having a thread or two a year to add a custom tag for a new language that’s gaining popularity?
And is the extra complexity of parametrized tags worth it, with respect to both UX and implementation?
How would you see tagging a story work out? Is it a freeform language field? Any length and character set limits? How do you deal with differing spellings of a language?
Tags have categories. Maybe there could be a checkbox to check/uncheck them all at once, without impacting tags-as-scope.
In addition to that, maybe we can also let users specify regex to match tags they want to filter?