Shoreham can not be a light bulb moment where people suddenly realise that aircraft traveling at 2,3,400knts eat up a lot of random space if it goes wrong and have a lot of energy. If that is a light bulb moment then we need to change the people who regulate this stuff.
If it was a light bulb moment, the light bulb is brightly on now!
The considerations which were not highlighted during planning, and allowed circumstances which became fatal, are known, and already specified in airshow planning - I've done it. Someone did not think enough, and a regulator accepted that. It was a failure of imagination. Imaginations will be much more effective next time - worldwide.