Reports filtering "not equal to __" should also include unassigned/null results

I was looking to run a report that included tasks not assigned to a list of teams. This report also unexpectedly excluded unassigned tasks. Basically if you have a filter set to “not equal to X” you may not be able to count on it including results with null values (which are obviously not equal to X). I observed this in assignments reports for tasks that had a job role assigned, but not a user assigned, not sure if similar behavior occurs elsewhere.