I looked at all the photos again, the sling boats didn't do well.
Were they blowing in the wind back and forth ? They all couldn't have been clipped by other boats. Or did the water level raise them partially out of the slings?
Since I don't see any pilings disloged and the overhead structure survived, perhaps the sling mounted boats would fare better if lowered in the water and secured to the pilings with double lines and more fenders just in case, in a pinch run down to the town dump and get some spent tires. Perfect as storm fenders if you need more.
Not everyone can get their boat out nor have a place to go.
There is a few commercial looking boats that sank, incl. the one with the tires - some kind of towing vessel. Did the commercial guys spend less time securing, double lining, etc. ?
My entire discussion is intended for damage avoidance in next event, and there will always be a next event.
Nothing we can do about what has expired. There is a silver lining in every cloud, IMHO, in this case, lesson learned for next time around.