The CLI itself is not being deprecated. The risk is narrower and operational: stale Linux repository keyrings can stop package installs or updates from verifying after the old signing key expires.
PGDG's 20 October repository retirement requires RHEL, Rocky and AlmaLinux 9.6/10.0 operators to update their OS minor release or deliberately switch to the frozen archive. Rolling EL9 and EL10 repository packages are unaffected.