It sounds like the categories are almost treated like separate communities? That’s not an incredibly common way to use Discourse, which is why we don’t currently have category-specific moderation features.
Generally if someone is acting poorly it’s a detriment to the entire community, regardless of category, which is why the standard action is to silence them globally.
Category-specific moderation has been discussed previously, and might one day be available, but there’s no current timeline for implementing it: Category-Specific Moderators, phase 1 RFC and Category-Specific Moderators, phase 2 RFC