An apologist would argue that leaving the sensors to degrade and leach into the environment or for ones with buoyant parts to possibly break free and endanger seagoers is not better than deconstruction.

The malicious belief would be that it's to ensure that the system can't be easily reactivated and that a non-profit couldn't offer to take over the running costs, there's also the possible "benefit" of redirecting funding that has already been allocated for marine science that would be harder to not dispense rather than arguably use it for this.