I mean, sure, except that many large open-source projects (e.g. Linux [1], Nixpkgs [2], etc) require this as part of their AI policy. Omit attribution in your own projects if you want, but the maintainers of these projects are owed at least that level of transparency for contributions.
Notably though, Linux's requirement (Assisted-by) is different from what Claude Code actually does (Co-Authored-By). I'm not sure, but it might be intentional (to make the signaling explicit).
For sure, and in the PR description for the Nixpkgs AI policy, they explicitly mentioned this as a "brown M&M test" [1]. I read the blog post as being against including this information in commit messages at all, not just about tools adding it automatically.
My projects also require Assisted-by attribution as that's what the Fedora AI policy requires and that was the first major org with a coherent AI policy that I found when choosing it. Not sure which came first, that or Claude hijacking Co-Authored-By.
Personally, I prefer Assisted-By. Co-Authored-By implies a level of respect and self-direction I don't think LLM's deserve.