Mine does not tally up at all, i currently have around 220mb of what I would class personal multimedia (images/videos/audio files) accessed via the battery and device care.
The properties of (my) media storage as shown in your picture is registering 9.12 GB.
Given that my phone is app heavy in terms of my storage used (navigation apps/games) I can only conclude that every piece of media from said apps/games are included within that app for easy access for the OS.
In regards of space reserved by the operating system its common practice for this to take place.
Gaming laptops that come with a 512gb (ssd) never have this space available because it reserves so much space by default to replace and bad blocks it may encounter during usage and the operating system takes the rest, external usb drives behave the same way. In a ideal world a drive should come with the advirtised space with a safe reserve added on top but this is the way its always been.
I personally made sure I bought the 256gb version of (my) phone knowing that samsung removed the SDCard slot as I know the 128gb would get munched up to fast to be useful.
Edit:
For transparency I also have a bunch of audio books that aren't listed under audio in the data tree as they're in a folder labeled audio books (none default location) and my home cctv app tends to fill its own debug folder with cached images on my camera when I view the feeds, which i have to clear out manually or they get out of control
The properties of (my) media storage as shown in your picture is registering 9.12 GB.
Given that my phone is app heavy in terms of my storage used (navigation apps/games) I can only conclude that every piece of media from said apps/games are included within that app for easy access for the OS.
In regards of space reserved by the operating system its common practice for this to take place.
Gaming laptops that come with a 512gb (ssd) never have this space available because it reserves so much space by default to replace and bad blocks it may encounter during usage and the operating system takes the rest, external usb drives behave the same way. In a ideal world a drive should come with the advirtised space with a safe reserve added on top but this is the way its always been.
I personally made sure I bought the 256gb version of (my) phone knowing that samsung removed the SDCard slot as I know the 128gb would get munched up to fast to be useful.
Edit:
For transparency I also have a bunch of audio books that aren't listed under audio in the data tree as they're in a folder labeled audio books (none default location) and my home cctv app tends to fill its own debug folder with cached images on my camera when I view the feeds, which i have to clear out manually or they get out of control
