@sharepointuser-5603 - Thanks for the question and using MS Q&A platform.
The board view is organized by a column, and empty buckets of board view are generated by values of this column. It's by designed, there is no option to remove it.
You could submit your suggestion in the feedback portal.
Workaround : You can remove this empty buckets by removing this value from the column choice! but you will loose this choice
Hope this helps. Do let us know if you have any further queries.
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