Remove the Logged-in User from Multiple Collections

You could make this bulk reset via countdown timer trick. The tutorial for mass update of the records in the list is here:

You could implement the same logic - upon pressing a button, direct user to a separate page with the list of tasks, and then create a timer-based action to update each task accordingly.

You’ll not be able to store the history of task completion though, but as I understand you don’t have such requirements.

Best,
Victor