That’s what somebody told me, at any rate.
It would seem to me that it should be viable to create a black box that can detach itself from the plane, in the event of a water landing, and have it float to be picked up.
For the amount of money that was spent trying to find this plane they probably could retro-fitted half the planes in the world with such a design.
There is one aircraft in service with such a system even though it’s military. The problem is pre-mature ejection. We have left the data recorders in the Atlantic a few times. The top of the tail is an airfoil that can glide and make a soft landing. You are still faced with a large search area which the actual rest of the bird can be in
The system has been in use since late 60’s.