You can now control how many items appear in a chart series within dashboards or record report charts.
Set a "displayed items" limit per chart with the following maximums:
Bar chart: 100 items
Pie chart: 50 items
Stacked bar chart: 25 items
Stacked chart: 25 items
Then, optionally show/hide any data beyond the limit as a single "other" bucket, keeping your charts clean without losing the full picture.