Drill Down Timeline PRO can automatically aggregate your data depending on your selected time units. Use the default Power BI date/time unit hierarchy or build your own using the Date Hierarchy field, and then head to the Display Units section in the Format Visual tab to select which time units are displayed in the initial view and which time units can the user drill down to.

The visual will aggregate the values into larger time units depending on the current view. The user can then simply drill down and explore the data in closer detail.