Watch those videos.

Now design me an automated deployment system which can handle the operating conditions and environment, and respond, effectively, as good or better than a human can.

Consider that your ladder can get snagged, caught, swing in the wind or seas, collect flotsam or jetsam, etc. Things can get very squirrely at sea.

Sometimes humans aren't the best at a specific function, but through processing and manipulation capabilities, including the ability to use and apply multiple other tools, they're the best means for responding to a general case of circumstances which cover a lot of ground.

I'd say specifically this case doesn't seem very safe to me. For example you could have a rope attach to some rod on the boat, then you could use that rope to attach some climbing device. Of course, the rope has to be lowered slowly and the receptacle must be large so there isn't much to miss.

Not hard to imagine something better than jumping to a ladder on the side of the boat to be honest.