Donald made an interesting suggestion over on https://github.com/pypa/packaging-problems/issues/127#issuecomment-374401331, which was to have distutils stop overwriting the Author metadata with the Maintainer metadata when both are specified and instead emit a warning about an unknown keyword argument.

I'm not sure we'd want to change the behaviour of mapping Maintainer -> Author (since it's a nice way to retain credit in the code, while changing the metadata on PyPI to reflect the current metadata), but I *do* think it would be reasonable to have distutils emit a warning that metadata version 1.1 can't represent the maintainer information properly, and folks should upgrade to using setuptools instead.

Éric, your thoughts?