First step would be to get rid of the warning in the zipfile docs and replace it with the info that the absolute path '/' and any relative path are stripped silently before the file is extracted.

It would also be worth adding an enhancement to zipfile to optionally not do it silently.

I hope the same considerations apply to tarfile, but I haven't checked.

In other words, I do think that code is a holdover from when zipfile *wasn't* safe, but since I didn't write it I don't know for sure.