You are dead right that legislation is the only answer to the problem.
It has to be accepted that in today's highly competitive industry with executives that simply don't understand what they are managing ( how can you if you have never done it) the legal maximums are the target. We have to have sensible legal maximums in order to achieve sensible rosters.
The efficiency of the systems in place will be quickly honed due to the power of the almighty dollar right up to whatever limit is set.