If you use a reverse workflow using keyboard shortcuts you can use:
j k to highlight each row. Then b to bookmark what you care about.
I am not against allowing a “quick” dismiss using keyboard shortcuts that flicks a topic you were once tracking into Normal similar to how bookmark works but it is a bit of a ninja feature for a very very specific type of users, plus we would need to worry about undo there, the UX is not crystal clear even for a power user.