If Git started not committing some files in a directory without user input, based on conventions of an OS or programming language that you might not be using, t

If Git started not committing some files in a directory without user input, based on conventions of an OS or programming language that you might not be using, that would seem like quite the ad-hoc side-effect. I would definitely vote for a way to incorporate sane .gitignore settings per-OS or per-language, but still make it opt-in.