I'm a PC user who is helping a friend who has a Mac problem. He has a 2017 MacBook Pro, 15-inch, 10.13.6, 1 TB. The problem is that he only has about 2 GB disk space remaining.
Using About This Mac > Storage > Manage..., the following is reported, in GB:
Applications: 6.72
Documents: 440.03
iCloud Drive: 4.59
iTunes: 114.75
Mail: 2.78
System: 425.56
I'm surprised at the large amount of space used by the system. I'd like to review that folder, but it is greyed out in Finder.
How can I make sense of the large amount of disk space used by the system?
EDIT: tmutil listlocalsnapshots returns nothing, so this does not appear to be a Time Machine issue.