There is another way of people learning the consequences. Natural Law! They continue to take undersized fish, no more fish left, lesson learned. Doesn't help us in our lifetime though.
There are far more fishos on Strike Hook than there are fishieries officers, it seems that we already have the resources, we all just need to grow the kahunas to use those resources. On top of that, Strike Hook fishos won't charge you a fee to participate in something that humans have done for thousands of years for free.