Why helicopters gave way to uncrewed mine countermeasures

Was airborne mine countermeasures a failed concept because mine-sweeping helicopters have rapidly fallen out of use?

No. Helicopters helped keep ships clear of mines, and capable uncrewed equipment now offers another way to do that. Different mine types and increasingly selective sensors also affect what a sweep can achieve.

Airborne mine countermeasures kept ships away from mines, and capable uncrewed equipment can now provide that separation without a crew aboard. Its loss is also easier to accept, although that same expendability can weaken its value for deterrence. Helicopter sweeping works better against some mine types than others, with magnetic and acoustic signatures presenting different problems. One suggestion is that a sufficiently sophisticated mine could recognise helicopter noise alongside a simulated target signature and withhold its response. That would require suitable sensors and processing, with consequences for cost and power demand. Encapsulated torpedo mines already contain more complex systems than traditional contact mines.