Revert "Tables cards are now public in AoG, enabling them"

This reverts commit 691c2bf8d9f84d1ed0a769a91a0735f5aa63d92f.
diff --git a/assistant_callback.php b/assistant_callback.php
index d74d27e..15b6f79 100644
--- a/assistant_callback.php
+++ b/assistant_callback.php
@@ -149,7 +149,7 @@
     } else {
       arsort($neighbors);
       $params = array("person" => $closest, "count" => (count($neighbors) == 1 ? $i18n->msg("count_singular") : $i18n->msg("count_plural", array("count" => count($neighbors)))));
-      if (conv::has("actions.capability.SCREEN_OUTPUT", $json)) {
+      /*if (conv::has("actions.capability.SCREEN_OUTPUT", $json)) {
         $items = [
           array(
             "simpleResponse" => array(
@@ -177,14 +177,15 @@
           $items[1]["tableCard"]["rows"][] = array("cells" => [array("text" => $neighbor), array("text" => (string)$votes)]);
         }
         conv::ask_custom($items);
-      } else {   // This code shows a table if the user has a screen, and
-                 // as of now tables are finally public!
+      } else {*/ // This code shows a table if the user has a screen, but
+                 // unfortunately tables are not public yet.
+                 // @TODO: Uncomment when tables are out of developer preview.
         $people = array_keys($neighbors);
         $people_string = comma($people);
         $params["edges"] = $people_string;
         $num = mt_rand(1, 3);
         conv::ask_followup($i18n->msg("edges_".$num, $params), $i18n);
-      }
+      /*}*/
     }
   } else {
     conv::ask_followup($i18n->msg("not_found", array("person" => $json["queryResult"]["parameters"]["Vertex"])), $i18n);