I flew jumpers for a few seasons, and this risk was a great concern. As the jump pilot, I was more aware than other pilots at the airport would have been. The jumpers were really good at avoiding the approach path, and runway itself, and I got really good at counting jumpers to account for everyone before I committed to the runway. The alarming even pictured is hard to call, but I'm not rushing to blame the pilot, I can believe that they were looking where they were going, and got a sudden nasty surprise. It's possible that a "jumpers away" call from the jump plane could have been minutes earlier, even before they were monitoring the radio before takeoff.
Though I never jumped, I am certain that a competent jumper could have heard and been aware of the Cessna beginning its takeoff, and being able to predict its path, and maneuver just enough out of its path to prevent a collision - being the jumper, there'd be good motivation! I do not consider the Cessna to be maneuverable enough to be able to have averted that collision at the last moment.