iPhoto. iTunes. iCloud. iMovie. Notes.

None use the file system in anything like the way their unix underpinning would have files be understood or organised for users. Hard to even know where your files are without asking the app to deal with them one by one. Predated phones and even Spotlight doesn’t do a good job of showing/knowing where your files are.

And why should they? I don't know where my browser cache is either. Or my rows in my sqlite database. Or the system clock configuration. Actually I do know: They're stored on the hard drive.

Files aren't physical.

Diff two iPhoto libraries to check if they contain the duplicate photos

Create a new library,

import the images from both libraries (https://support.apple.com/en-us/119920)

View > Utilities > Duplicates

or use jdupes or czkawka on both directories.

Great tip, but also: exactly.

On the phone itself?

On the filesystem-enabled device called Mac commonly used for semi-pro operations like file management and backup.

> And why should they? I don't know where my browser cache is either.

This makes it a pain where you want to have a custom configuration. Like moving the cache to a ramdisk. My NVME disk is plenty fast, but rarely I want my browser cache to persist across a reboot. It's a pain to move the cache to /tmp/firefox-cache as an example (/tmp is a ramdisk on my laptop). Also a pain to backup profiles.

i know where mine is, so i can clear it myself if i care.

So which is it? Is Apple not responsible for ditching the filesystem, or is it a good thing that Apple has ditched the filesystem? You can't have it both ways.