I'm pretty sure it won't happen
Most of these players are big gold players and morale would mean they can lose cities even when golding out of their behind
Actually, I recognize a few as some of those "I never lost a city" players, they defo wouldn't want to lose one because they can't break it
No morale worlds are not likely to happen any time soon, but if it does I'll be there with some buddies to see if these guys hold up on their "reputation"