1. Profit margins are so tight because truck businesses compete with each other. In this case, increasing safety standards in a uniform way, will not change profits since the costs can be passed on to consumers.
2. Profit margins are so tight because truck businesses are competing with other forms of transport. In that case, imposing more safety standards will result in less business being done by truck, and more by other means. As long as these don't have worse safety issues, this would be a good thing.
You are right the revenue is a meaningless figure in both cases.
1. Profit margins are so tight because truck businesses compete with each other. In this case, increasing safety standards in a uniform way, will not change profits since the costs can be passed on to consumers.
2. Profit margins are so tight because truck businesses are competing with other forms of transport. In that case, imposing more safety standards will result in less business being done by truck, and more by other means. As long as these don't have worse safety issues, this would be a good thing.
You are right the revenue is a meaningless figure in both cases.