MariaDB repositories for RedHat el8 and el9 like systems do not include MariaDB-client-compat and MariaDB-server-compat packages since 11.4.5. This means that 11.4.5 cannot be reliably used to upgrade to from previous versions (< 11.0), since some user scripts may rely on MySQL-compatible utilities naming. Thus, such upgrades are effectively blocked.

The packages were present in 11.4.4 and earlier versions. E.g. compare:
1. https://dlm.mariadb.com/browse/mariadb_server/11.4.4/yum/rhel/9/x86_64/rpms/
2. https://dlm.mariadb.com/browse/mariadb_server/11.4.5/yum/rhel/9/x86_64/rpms/

Can be checked on a test system using a command like `dnf repository-packages mariadb-main list | grep compat` or `dnf install MariaDB-client-compat MariaDB-server-compat`.

The packages were added in scope of MDEV-30203.