The zip module is outdated and buggy - hell there's even a list of bugs on its module page (https://dlang.org/phobos/std_zip.html).
This should be removed from Phobos as it can be done a lot better as a user package and is a quite seldom use case. See e.g.
https://github.com/rcythr/archive
Comment #1 by bugzilla — 2019-11-20T17:57:30Z
With the recent bugfixes and improvements, I hope it's OK, to keep it. :-)
(If there is a better version, I would not mind, if it were replaced some day.)