According to this help page (https://help.salesforce.com/articleView?id=sf.reports_administrative.htm&type=5), the All Pending Approval Requests report should be viewable by any user who has View Setup and Configuration permission. I made a clone of this report, and put it into a folder. When I try and view the cloned report as a user who has access to that folder and whose profile has View Setup and Configuration checked, I get an error (you don't have sufficient privileges to perform this operation). So is there something I am missing? The report I cloned is for knowledge approvals; the user I am testing is able to see the approvals and approve them.
Per posts on this question, in order to run the
All Pending Approval Requests report, or saved clones of it, the running user needs to have
View All Data permission.
I confirmed this by adding View All Data to a clone of the Standard User profile, seeing the report run successfully, removing the permission from the profile and then seeing the Insufficient Privileges error.
As you suggest, this is rather frustrating as the user can see their approvals without View All Data, and the report can be configured to (e.g.) only show "My Approvals". Also profiles for Platform Users can't be given the View All Data permission, even if you decided it was an appropriate workaround to grant access to the report.
I think the article is trying to say that you need the "View Setup and Configuration" permission to see the "Administrative Reports" folder, and then the content of that folder is dependent on other permissions, but I agree it's not 100% clear.
One common workaround to share reports which require admin permission to non-admin users is to Schedule the report to run as one user and be sent to another. Unfortunately when I try and subscribe to a report of this type my screen locks with a spinner.