The recent changes to trials and ports are going to cause an inbalance until the server cap catches up. Right now those who already unlocked Cursed levels keep access to them. But those yet to beat them are now locked out for the foreseeable future.
This means top players will continue to widen the gap simply based on having better rewards available to them (yellow badge bits, colossal xp drops).
These are huge advantages. Why not allow the player to unlock the next level if they 3 star the level prior.