An RFC has now entered its Final Comment Period. In 14 days, discussion
will end and the proposal will either be accepted, rejected or withdrawn:

https://gitlab.archlinux.org/archlinux/rfcs/-/merge_requests/40

Please visit the above link for discussion.

Summary:
Our package sources currently do not have explicit licenses.
This RFC proposes to license all Arch Linux package sources under the terms of the Zero-Clause BSD license.