I'm not sure what camera companies could have done short of to stop being a camera company and being a phone company which seems unrealistic. They only have experience with cameras, not with the amount of software dev needed to ship a competitive smartphone.

What did livery owners do when the car came? They closed shop is my guess.

I don't really think there is much the camera companies could do. They've tried making it so you can use your camera from your phone. It's too cumbersome. They've tried making it so you can post images directly from the camera to the various services. Again too cumbersome. I have my phone always. I rarely have my camera. They've added apps stores to their cameras. They've added APIs. No one cares, it's not enough. Except for a few pros they're just not something anyone needs anymore.