Boy you really like painting pictures with broad strokes don't you. We have size limits which is very effective at maintaining the fishery.
If people are going to poach they are going to take them with or without a notched tail - so that wouldn't matter
When I look a the Northeast commercial fishery and compare it to the Florida Commercial fishery and then compare that to the Caribbean commercial fishery, I see the following.
The New England fishery is made up of associations, who vigorously defend "their turf", but also police each other, as they know that the North American Lobster is a limited resource, and they have lived through hard times when the catch was down, the price was high, and fuel almost put them out of business. Someone sat down and thought about what it would make to make the fishery sustainable, so they outlawed recreational take on Scuba, they limited recreational take by trap to 5, and they made sure that the eggers were notched, so no one took them even when it was otherwise legal to do so. The Maine fishery is now landing more lobsters that at any time in the past, and the prices are high. Traps are not allowed to go "ghost", because you have to turn in over 90% of last years trap tags to get your trap tags for the next year. Entry is limited. You must be a stern man on a working boat for 3 years before you can apply to set your own traps.
Lets contrast that to the Florida commercial fishery. Traps are abandoned on the reef to continue fishing without regard to retrieval. Any idiot with a boat can get a 2000 trap license and set traps on the coral, in the backcountry, wherever you want, and the state protects your right to fish in a stupid manner. Many commercial trappers go out and build casitas (lets not get into a argument about whether casitas are right or wrong, lets just say that they are illegal) in the sanctuary and clutter up the bottom with old cinder blocks, car hoods, and a host of other crap that all moves around in a storm and impacts the coral. A lobster boat is limited as to haw many they can take, so they just go to another fish house to unload if they catch too many. The price is well up this year, not because of some strict conservation measure, or because lobsters are scarce, but because these knotheads finally figured out how to keep the lobsters alive on a boat, something we've been doing in New England since 1922. Those live lobsters aren't feeding Americans, BTW, they are headed straight to China. If I want to go out and do a reef cleanup, I can take the pot warp, and I can take the broken traps, but I am not allowed by Florida law to touch a fishing trap, even if it had 1000 dead lobsters in it. I can't even get a permit from FWC to do so. The Sanctuary Superintendant can't get a permit to do so in his own sanctuary. That's how much the FWC protects the fishery, by protecting ghost traps.
Lobsters in the Caribbean are typically taken by divers to satisfy the American restaurant chain market like Red Lobster. They are taken on scuba or hookah, which limits the take to the top 200 feet or so. Taking lobsters on scuba is horribly inefficient compared to trapping, so there are plenty of lobsters left to maintain the population. Say what you want about the Moskito indians, they aren't very good at wiping out lobster populations.
Size limits don't maintain the fishery. These lobsters caught in Florida don't come from Florida, they come from the Yucatan, Belize, Honduras. Very little lobster larve settles out here from lobsters that spawn here.