To clarify, I'm not condoning annoying spam but if say e.g. Netlify or GitHub added a ".git folder should not exist on a public site" lint rule when you personally deploy your site, I would say it would be a net benefit.
> There's plenty of cases where a .git directory is just harmless
Pretty much all lint rules have false positives so this isn't a good yardstick. Can it potentially cause harm when you do it and is there's no beneficial reason to do it? If yes to both then it's an ideal candidate for a lint rule.