Why do we need "Administrator" role to monitor IBM Storwize and SVC?

The problem is that one command which is necessary for downloading of statistical data requires Administrator role.
It is command: svctask cpdumps
The cpdumps command copies dump files from a nonconfiguration node onto the configuration node.
Data can be retrieved via scp only from the configuration node.
The problem is same for getting of data through CIMOM or TPC.

Storage firmware 8+ brings RestrictedAdmin role

It is a step forward, use that role instead of "Administrator".
Role desciption as per manual: Users can complete the same tasks and run most of the same commands as administrator-role users. However, users with the Restricted Administrator role are not authorized to run the rmvdisk, rmvdiskhostmap, rmhost, or rmmdiskgrp commands

Storage firmware 8.3.1.2+ and Monitor role

Since that storage firmware there is no problem to use Monitor role.