One common use case for WikiPage is accessing the current revision's content. If we want to stop passing around instances of WikiPage, and instead pass around PageIdentity or PageRecord, we need an easy way to access the current page content.
Interface draft:
interface PageContentAccess { public function getPageContent( PageIdentity $page, Authority $authority = null, $role = SlotRecord::MAIN ): ?Content; }
The implementation can essentially be a wrapper around RevisionStore::getRevisionByTitle()