dimatematik [1] filed a deletion request for cmp-nvim-lsp [2]:

Upstream repository does not provide releases, there is neovim-cmp- nvim-lsp-git package with same source, so it's not necessary to maintain "stable" version manually linked to commits. Last updated in 2021, orphaned, impossible to build due to an error in PKGBUILD, seems like users and maintainers are not interested in this

[1] https://aur.archlinux.org/account/dimatematik/ [2] https://aur.archlinux.org/pkgbase/cmp-nvim-lsp/