In every work related org-file, I set the category like this: 

#+CATEGORY: work

I then use org-agenda-custom-commands like those below to show work related content or not work related content. This works in Org version 9.5.5/Emacs 28.2, but in Org version 9.6.4/Emacs 29.0.90, both custom-commands shows the content of every file, category "work" or not.

I posted this on Reddit, and according to a user it can be reproduced in the stable version, while it works fine in the development version.
My org-agenda-custom-commands settings looks like this: '(org-agenda-custom-commands   '(("p" "private"      ((agenda "" nil)       (alltodo ""		((org-agenda-category-filter-preset		  '("-work")))))      nil)     ("w" "Work"      ((agenda "" nil)       (alltodo ""		((org-agenda-category-filter-preset		  '("+work")))))      nil nil)))