Accidents "waiting to happen" like this seem too frequent for comfort. I spent my working life in the oil industry where Safety is paramount, and such an accident frequency as this would not be tolerated.
The quick fix is a safety harness, if properly adapted for the task it would be easy to use and give the user the confidence to lean out and not trust the steps. The user should be educated to the fact that Spiros and Co., sometimes drives away and ladders are therefore not safe.
The long term solution is a door opening and closing system which is automatic. If it cost a couple of million dollars to design,(one off cost) and say a quarter of a million to install it is peanuts in the overall cost of the aircraft.