Fair enough, but the issue is not the slug, the slug works fine.
the issue is dealing with referencing the category name when it contains spaces in either the search or in text.
I presume this is why Categories have a slug (short, URL safe) and a title (user visible).
My problem is that with a user visible title with spaces, it is difficult/impossible to use as a reference in text or searching.
Specifically, it would seem useful to reference a category in the text of its post with the full title since it is use visible.
I suppose if I had a slug “questions” and a title “Questions & Feedback”, and I typed into a discourse post “quest” and it does its nice pop up thing and inserts #questions and then displays to the user the title in the markup render, that would be a solution. The problem as it stands is that it displays #questions, using the slug (intended presumably for use in URLs) in a user visible location rather than the title. If it displayed it something like #Questions & Feedback (or some other highlighting, perhaps using the category color), then the display would have no need for quotes, and the user would never really need to deal with seeing the slug (even though it would be there in the raw text).