Currently:
$ grep wgDisableAnonTalk * -R
includes/DefaultSettings.php:$wgDisableAnonTalk = false;
includes/Linker.php: global $wgUser, $wgDisableAnonTalk, $wgLang;
includes/Linker.php: $talkable = !( $wgDisableAnonTalk && 0 == $userId );
$
So it's only a visual hack. The whole feature should be disabled by not checking user_newtalk at all.
Version: unspecified
Severity: normal