About 30 years ago I had an incident where I hit a boat. I was driving an older four door Toyota Land Cruiser and was just leaving a boat launch area after a day of fishing. About 5 boats all pulled out in a row, I was the last to leave the ramp area. The guy ahead of me was towing what I think was about a 16' Sea King. As I headed out of the ramp and got up to speed, I noticed his boat move a bit on the trailer, as I started to point out to my buddy sitting in the passenger seat about the idiot ahead of me who didn't tie his boat down, the thing jump up off the trailer and landed sideways in front of me just feet in front of my truck.
I had no time to react, at about 50 mph I hit the boat, all I heard was a loud pop sound, then all I saw was fiberglass bits sliding over the truck. I pulled over, (as did a State Police Officer who had been about four car lengths behind me). The guy who owned the boat came over screaming that I ruined his boat. The outboard was lying in the road, the police car that had been behind me was covered in fiberglass bits, as was my truck. My home made brush guard on the truck took the brunt of the hit, the only damage to my truck was a tennis ball size dent in the left side of the hood where something solid came through the bars on the brush guard.
About 90% of the boat was broken into pieces no bigger than a squirrel. The few larger pieces flew into the woods, and there was some busted up plywood still bolted to the old Chrysler motor. The motor controls were in the grille of the police car, the officer seemed to think that they were what bounced off my hood leaving the dent.
As the owner of the boat ranted and raged about how I destroyed his boat, the officer gave him a seat in the patrol car since he wouldn't stop screaming.
I never followed up on what tickets he got, the damage to my truck wasn't worth an insurance claim, and I was never summoned to court over the incident.
I'm sure the damage to the patrol car got him some hefty fines and a few tickets. The officer took my info, and told me I was free to go at the time unless I wanted to press civil charges against the driver. I saw no point and just left. If I had been driving a small car, I suppose the outcome would have been different, but the old Landcruiser was a well used old truck with a huge home made winch bumper and brush guard made from 1 1/2" tubing with braces run down to the frame through the fenders. The PTO winch, the grille, and the snow plow mount made the front of that thing pretty much indestructible.
A good number of people out there who tow boats, or any trailer for that matter have no idea what is safe and what isn't.
Take a look around at some of the rigs on the road. I had a customer years ago who's trailer coupler had fallen apart, he drilled a hole through the top where the ball goes and just bolted it to the step bumper. He towed that way for years. No safety chains at all, his theory is that if it broke loose, he didn't want it chewing up the tailgate on his truck.
How many people don't look to see if the coupler takes a 1 7/8" or 2" ball? They just drop the trailer on, if it latches, down the road they go.
How many have no idea that the coupler can be adjusted to fit the ball properly?
How many people would even notice if the spring in the coupler latch broke or was missing? How many even bother to put a lock or bolt through the coupler when towing? How many people are towing trailers on rusted out step bumpers with no idea what could happen if it failed.
Chances are that boat in the video was never attached properly, either the wrong size ball, or a bad coupler latch, or it may well have never been down on the ball in the first place. I followed a guy about four miles once to the boat ramp, he pulled out of a gas station just ahead of me and was in front of me in line to launch. He stopped while in line, untied the boat, tossed all his coolers and gear in the boat then proceeded back down the ramp, as he did, the trailer reared up and the outboard hit the ramp. The trailer came off the ball. I ran over to help and the trailer coupler still had a lock through the hole, and the ball was the right size. When we manhandled the trailer back onto the ball, I latched it on there myself and it fit secure. The only explanation was that he never had the coupler all the way on the ball when he latched the handle and put the lock in. When the weight shifted on the ramp, plus the addition of all the gear he tossed in the back, it lifted right up. The tongue weight was enough to allow him to pull the boat down the road even though the coupler wasn't connected correctly.