A guess of mine is that life doesn’t try to destroy its living surroundings. If the contrary were true life would not survive very long any way. So from this I formulate a simple exaggerated guess.
All life trough evolution tries to improve its living surroundings. This then would mean that fish is important for the sea floor as the sea floor is important for the fish.
In this case there should be research into how different fish can take part in the recovery of the sea floor.