Symbols can be clicked on repeatedly now, so if someone mashes they will lose points as expected. I'm also resolving a timing issue that I missed that happened with a single player, where they'd start the game immediately on connection (since all players were connected) but before the SymbolContainer could call Start to subscribe for the game start message.

Assets/Prefabs/InGame/SymbolContainer.prefab

   m_Script: {fileID: 11500000, guid: 73a6c5df5c3139e448d76f8918fece73, type: 3}
   m_Name: 
   m_EditorClassIdentifier: 
+  m_rb: {fileID: 6367926983050135602}

Assets/Prefabs/InGame/SymbolObject.prefab

   m_IsTrigger: 1
   m_Enabled: 1
   serializedVersion: 2
-  m_Size: {x: 2, y: 2, z: 0.2}
+  m_Size: {x: 1.75, y: 1.75, z: 0.2}
   m_Center: {x: 0, y: 0, z: 0}
 --- !u!114 &-8192876538761676823
 MonoBehaviour:

Assets/Scripts/Game/InGame/PlayerCursor.cs

             if (m_currentlyCollidingSymbols.Count > 0)
             {
                 SymbolObject symbol = m_currentlyCollidingSymbols[0];
-                m_currentlyCollidingSymbols.RemoveAt(0);
                 Locator.Get.InGameInputHandler.OnPlayerInput(id, symbol);
             }
             OnInputVisuals_ClientRpc();

Assets/Scripts/Game/InGame/SymbolContainer.cs

     [RequireComponent(typeof(Rigidbody))]
     public class SymbolContainer : NetworkBehaviour, IReceiveMessages
     {
-        private Rigidbody m_rb;
+        [SerializeField] private Rigidbody m_rb = default;
         private bool m_isConnected = false;
         private bool m_hasGameStarted = false;
         private void OnGameStarted()
                 BeginMotion();
         }
 
+        public void Awake() // If there's just one player, Start would occur after the GameBeginning message is sent, so use Awake/OnEnable instead.
+        {
+            Locator.Get.Messenger.Subscribe(this);
+        }
+
         public void Start()
         {
             if (!IsHost)
-            m_rb = this.GetComponent<Rigidbody>();
-            Locator.Get.Messenger.Subscribe(this);
             GetComponent<NetworkObject>().Spawn();
         }