Mental clutter gets blamed on character. Too weak, too online, not serious enough. That story is flattering to the people who feel clear today and useless to everyone else.
Fog is usually a design problem. Too many open loops on the same surface. A phone that lives on the pillow. A morning that begins with other people's urgency. The mind is not broken. The room is arranged so that attention never lands.
Change one surface this afternoon. Put the phone in another room for the first hour. Write the three things that are actually open, and close the tab on the rest. You do not need a new personality. You need a quieter table.