Can you tell more? I would be interested how you can get management to let go of regular estimations, and how you still delivered.
As long as your team manages to finish sprints, it doesn’t matter how you are estimating (or not) the tasks inside of a sprint.
Sprint tasks are for internal (team) use only, including the management inside the team. But people outside (and up) the team just need your deadline commitment.
They have to convince themselves.