If you try to mount an cifs shares on AlmaLinux 9 and get the following error message

[tux@server]$ sudo mount -a
mount error: cifs filesystem not supported by the system
mount error(19): No such device
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs) and kernel log messages (dmesg)

then you are missing the required kernel-modules.

You can install them like this.

dnf install kernel-modules

After that you should be able to mount the share.

This solution is based on this reddit thread.