I’ve seen concerns and FUD over getting lost in too many tasks. How do you manage the overhead of 20 4-hour tasks against 2-3 high level tasks?
But you are right that estimates are for managers. Managers should watch their reporter's progress and use that as evidence to build evidence. If the first task of 20 took 1 week, it's a 2year project. Update estimate as time and progress and work remaining increases.