This came up in T194707#4448979
It's often the case on English wikipedia that an event- or project-specific category is applied to the Talk page for an article instead of the article page (e.g., see the category All WikiProject Women in Red pages, which is composed entirely of talk pages). But when users want to track edits made to a category, they want to see edits made to the article page, not the talk page.
Proposed solution: Make it so that users can include talk-page categories when setting their filters. The system will find the talk pages, but then behave as though the categories were applied to the associated main namespace pages. I.e., the main page pagename will be the one listed in reports, and all statistics (e.g., # of edits made, etc.) will be gathered for main namespace pages only.