"How is this information not helpful?"
Because that information is about a CAR not a BOAT. There is no equivalent of Carfax for boats, because the states and insurers do not keep and exchange data on boats the same way that they do on cars. And it is might simpler to not report a boat accident, as compared to a car where someone always see the accident, calls the police, and the incident is now reported and on file, like it or not.
I never said Carfax wasn't useful--but even for cars, it is not what you think it is. There are large gaps, errors and omissions, and Carfax does not respond to them. They showed a duplicate title issued for my own car, which surprised me since I was the only owner. I tried to contact them to ask what was going on and if in fact someone had pulled a duplicate (which can be used to "wash" the forged VIN number on a stolen car) and never got any response from them. Proving that they sweep data bases, garbage in garbage out and nothing more.