MarsSeed [1] filed a deletion request for ros-noetic-unique-identifier [2]:
Broken EOL empty metapackage release from 2017 [a], fails to build. [a]: http://github.com/ros-geographic-info/unique_identifier/tags [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/ros-noetic-unique-identifier/