Please have a hidden field/property for the ListItem object named "UniquePermissions" or something so that while fetching the list items we can filter based on this field/properrty. We have SharePoint Online Document libraries having more than 100,000 items and to run a Unique Permission report using PowerShell takes huge amount of time and most of the times it is throttled and connection is ended. It would be great if the existing fields "SharedwithDetails" or "SharedwithUsersId" be used for this , don't know what purpose they solve currently as some random information is retured in that field.

The field can be simply a true/false flag so True for item with broken inheritance and false for inheriting permission from parent. So if True then we can fetch "roleassignments" and create a complete report.