Artie, what missing about Daisy Disc? It seems default About Mac, storage is a simpler, nicer interface? Am I missing something?
This thread got a little diverted from Key's original question. So to get back to his question, I am going to attempt to answer this particular question.
What I think you are missing is
About This Mac > Storage provides the same data in text form that Daisy Disk, Grand Perspective, and Disk Map Analyzer presents graphically. In fact,
About This Mac > Storage does something the other three do not offer, which is an alternate interface to System Preferences > Apple ID > iCloud Drive > Options and monitors Storage optimization and automatic trash emptying. All of these apps have a
reduce clutter function. It probably should be noted that much of this functionality is new to
about This Mac > Storage and got accustomed to the third-party apps before it was available in
About This Mac.... To be honest, I was unaware of the enhanced functionality in
about This Mac > Storage until you brought it up.
Back to your original question of iCloud Drive taking space on your internal boot drive, when you have Documents and Desktop stored in iCloud a mirrored copy of as many of those files as possible are kept on your internal boot drive to speed access to the data in the files, so the files occupy space on your internal drive and your iCloud drive. When your internal drive gets too full, the least recently accessed files on the internal drive are deleted to make room on that drive for more files, but a link to the file on iCloud is stored in the file directory and the only functional difference you might see is the file might take a little more time to load. So, all the files in your Documents folder will occupy space on your internal drive AND iCloud drive until your internal drive runs out of space, at which point some files will exist
only on iCloud but will remain accessible as if they were on your internal drive. The duplicate files are stored on iCloud in two folders, cleverly labeled Desktop and Documents. Both are exact mirrors of the folders in your user account.
NOTE: You can edit the copy of a file on iCloud, and its replicant on your internal drive will change as well.
