But what's wrong with calling that folder "Pictures" (or, even better, "pictures")? macOS calls it "Pictures".

"My" is used to make it clear that it contains the user's pictures, not pictures from other people, Apple, the Internet, etc. Just "Pictures" would make it more ambiguous. (Not saying it's the right thing to do, just pointing out why they do it.)

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hahn-kev 3 hours ago | parent [-]

If that's the case then there should be another folder to put pictures that aren't mine.

	▲	toast0 3 hours ago \| parent [-]
		In Windows, with the right settings, you might have a 'Shared Pictures' folder or a 'toast0's Pictures' folder.