Comment by ctippett

Correct. It's not so much "modern macOS" though, it's a feature of APFS[1].

  > Most of us still think of file systems in simple terms, like HFS+. Duplicate or copy a file, and macOS copies all the data to a new storage area and makes that a different file. Thankfully, APFS is much smarter than that, and regularly – indeed, as a rule whenever it can – doesn’t copy any data at all. What it does is create a clone file, which is a bit like a hard link, in that the file record points to the same data as the original. Unlike a hard link, the clone is a separate file, with its own iNode.

[1] https://eclecticlight.co/2021/05/29/explainer-deduplication/