This is my final post on this thread. I will continue in the more relevant thread. As I explained there:
Broad categories work fine, just plenty of noise. Later splitting into already ongoing subcategories is more of a wish than a feasible goal, unless for small communities, like Julia was last year. Tags work much better, as long as there is someone to properly apply them, still subscription-by-tag isn’t currently an option (if it becomes, we could really merge all categories, but we cannot convince people to use tags). Low traffic forums work fine, as much as people get their minds around the “quality over quantity” principle. And wikis don’t care about traffic (yes, Discourse is also a wiki). Furthermore, Julia community worked fine without Discourse and we wouldn’t have this discussion if it wasn’t for the migration. But the migration has good reasoning, explained elsewhere. To that reasoning, if we want to take full advantage of Discourse, neat organization is the way to go, turning this platform from parallel hosting to real integration.
Accordingly, I’d like to see categories for both ML and AI, but if noise prevails, it won’t be the end of the world.