Agile estimation isn't broken because of the techniques; rather, it is the thinking behind them.
Velocity is one of the most misunderstood numbers in product development; it reflects how much work a team completed in a Sprint, usually measured in story points.
Velocity is not a target but a result, meant to help teams answer questions such as consistency in finishing work and forecasting.
Using a range (best case, typical case, worst case) with velocity for forecasting provides flexibility, realism, and fosters conversations within the team.