Does PIM need inetd / xinetd to work correctly ?
It is possible to use the inetd / xinetd to allow seload to load seosd or other daemons configured in the [daemons] section of the seos.ini file, from a remote host having PIM installed.
For further info please see
By default the native packaging or install base to setup PIM is placing a relevant reference in /etc/inetd.conf to pull the rseloadd
However, all of this is optional - also note e.g. RHEL does not install inetd / xinetd when installing the OS minimally.
Still PIM is working without issue.
So to answer your question - PIM does not need inetd / xinetd to work correctly - if the above feature is not needed.