https://github.com/rails/rails/commit/785493ffed41abcca0686b...
Some devs will just open the first gitignore they see and throw stuff into it. No thank you.
This is not a complicated or important enough problem to justify a team-wide policy. Let it work itself out naturally.
https://git-scm.com/docs/git-check-ignore makes it trivial to debug repo-wide gitignore behavior.