I never knew that. How come they end up in Git repositories then? They shouldn't be visible to Git running on a native Mac filesystem?
`.gitignore` is for stuff that all developers need to ignore, like compiler output, and should be kept to the bare minimum.
But that is the case, all developers need to ignore the ".DS_Store" files. So by your own rule it is appropriate in there then?
Global .gitignore exists, but I just had to look it up again to refresh my memory – chances are, junior devs or hobby developers will never even consider it as an option.
That said, arguably ignoring .DS_Storage should be the default on macOS builds of git.
I can do the principled thing as you describe it. And then I can be angry every time a new dev arrives who doesn't have their computer correctly set up yet, or someone reinstalls their machine, or anything like that.
Or I can do the pragmatic thing, add one extra line to the .gitignore file and forget about it forever.
In my opinion this is not a hill worth dying on.
And, for what it's worth, all developers need to ignore .DS_Store files regardless if Finder creates it or it gets placed in when you unzip something created on a Mac, for instance.
In the best case, you spend extra time needlessly denying PRs and bothering people who already likely don't know git well enough to cleanly fix their commit. In the case of a repo large enough that you're not the only person approving PRs, I'd say it's almost inevitable that they eventually slip through.
Just my 2¢ from experience working in the industry.