Here are some use cases and examples:

We have a custom field with a date column that lists the date the item was created/imported. It would be really nice to simply be able to search for instances where that field is empty, but only date fields can be used.

Ditto on tons of other fields. Maybe we want to find items that do not have a part number. Etc.

If we cannot search based on this criteria, than it would be nice to at least sort based on it. As a sort could help us to find the empty fields since they would turn up first/last.

Thank You