With my PyPI administrator hat on, we have absolutely zero desire to ban anyone from PyPI for anything other than their actions on PyPI and in the Python ecosys

With my PyPI administrator hat on, we have absolutely zero desire to ban anyone from PyPI for anything other than their actions on PyPI and in the Python ecosystem (uploading malware, etc). If some class of users cannot use whatever signing solution we come up with, then we'll figure out an option for them or we'll scrap the solution completely.