Unable to mount NFS exports after updating RHEL 8 NFS server

Issue

• NFS exports no longer mount on NFS clients after updating RHEL 8 NFS server.
• nfs-mountd service fails after updating NFS server.

Starting the nfs-server service displays messages such as the following in /var/log/messages:

Sep 21 10:48:39 hostname systemd[1]: Starting NFS Mount Daemon...
Sep 21 10:48:39 hostname systemd[1]: Starting NFSv4 Client Tracking Daemon...
Sep 21 10:48:40 hostname systemd[1]: Started NFSv4 Client Tracking Daemon.
Sep 21 10:48:40 hostname systemd[1]: Started NFS Mount Daemon.
Sep 21 10:48:40 hostname rpc.mountd[96925]: Unable to watch /proc/fs/nfsd/clients: No such file or directory
Sep 21 10:48:40 hostname systemd[1]: nfs-mountd.service: Main process exited, code=exited, status=1/FAILURE
Sep 21 10:48:40 hostname systemd[1]: nfs-mountd.service: Failed with result 'exit-code'.

The status of the nfs-mountd.service may appear as the following:

[root@hostname ~]# systemctl status nfs-mountd
● nfs-mountd.service - NFS Mount Daemon
   Loaded: loaded (/usr/lib/systemd/system/nfs-mountd.service; static; vendor preset: disabled)
   Active: failed (Result: exit-code) since Wed 2022-09-28 10:48:40 PDT; 8s ago
  Process: 96889 ExecStart=/usr/sbin/rpc.mountd (code=exited, status=0/SUCCESS)
 Main PID: 96925 (code=exited, status=1/FAILURE)

Sep 21 10:48:39 hostname systemd[1]: Starting NFS Mount Daemon...
Sep 21 10:48:40 hostname systemd[1]: Started NFS Mount Daemon. 
Sep 21 10:48:40 hostname systemd[1]: nfs-mountd.service: Main process exited, code=exited, status=1/FAILURE
Sep 21 10:48:40 hostname systemd[1]: nfs-mountd.service: Failed with result 'exit-code'.