Accidents Will Happen - until we prevent them

Boats should be segregated from swimmers and people on inflatables.
Boats towing skiers and inflatables should not go round in circles enabling them to hit people, but only straight along strips of water.
An alternative is an A shape channel with a docking point in the middle. You leave the shore in the west and return in the east.  An observer with a megaphone should be observing the direction and safety of the people not in the towing boat but nearby in water.
Alternatively somebody should design a mechanical towing device like on ski lifts which pulls the inflatable or the skier without allowing other boats into the area.