Arch put out a statement saying users should update to a non infected binary even though it doesn’t appear to affect Arch https://archlinux.org/news/the-xz-package-has-been-backdoored/

However, out of an abundance of caution, we advise users to remove the malicious code from their system by upgrading either way. This is because other yet-to-be discovered methods to exploit the backdoor could exist.