I’d really like to be able to assign collaborators or assignees, or mass change the due dates, to an entire section within a project instead of needing to do it separately for each task in that section.
Welcome to the forum, @Amanda_Aiyar! Make sure you vote for your own request using the button near the title.
In the meantime, if you select multiple tasks (including the whole section), you can use the floating bar at the bottom to make mass updates to up to 500 tasks at a time.