Minor Currently no details about the affected user are displayed in the audit about user creation, update or removal.
This information is stored in the extended info with the "id" key.
So using a code like below displays it
<nuxeo-data-table-column name="[[i18n('audit.comment')]]">
<template>[[item.comment]] [[item.extended.id]]</template>
</nuxeo-data-table-column>
Setting the ticket as a bug as one can consider that it's a really important information missing for an audit.