I brought up this issue a number of years ago and it was partially resolved. See MDL-7158. Unfortunately, however, the main thing that I wished – for the ID Number to be displayed in the standard assignment submission display was not implemented. The complete grade display now does allow the student IDs to be listed, if this field has been ticked in the site admin/grades/user report (grade_report_showuseridnumber).

Would it be possible to allow the above parameter to also control the display of the ID number in the assignment submission display?

This is one of a number of tweaks that my university has implemented in their own way. We are attempting to remove ALL customization in order to allow upgrades whenever new security releases appear. Right now, there are so many points of customization, that the university has no choice but to "live dangerously" until the end of the school term.