First thought, on a quality treestand that is properly inspected for damage and properly maintained, I think the odds of one breaking are exceptionally small. The most likely reason for a fall is a mistake or misstep by the hunter. Lose your balance, or make a mental error when dead tired after going all-in five straight days during the rut. I think the most likely scenario is to make that human error and fall off the stand, but then I am hanging right there near the stand with a chance to climb back into a lock-on, or manipulate and move a climber so at least I can get on the platform. But also nothing is impossible.
That being said, some of these devices look pretty neat, my only concern is that it would be one more thing that needs to be learned how to use correctly. And remembered to be used correctly. Each little thing we add to the process gives us one more chance to mess up.
A closed mind keeps the truth out