Amphibious airplanes have a horrendous record landing on the water with the wheels down.
These accidents are completely pilot error for the simple reason they landed in the water with the gear down.
The real bad part of these accidents that are 100% preventable is they kill a lot of the occupants of the airplanes that land in the water with the gear down.
If you are a high time float plane pilot and you start flying amphibious airplanes you are at higher risk of landing with the gear in the wrong position for the surface you are landing on than a newly trained float plane pilot.