Maybe it's just me but it does seem like any bracing at all would have been better than none at all under a 100 gallon water tank.
I guess I was lucky the tank didn't fall through the rotten decking until I arrived at the RV park's check in shack.
This photo was obviously taken after I cleaned up the disaster, I wasn't really in the mood for photo taking during the check in process at the RV park while my tank was dragging on the road beneath the motorhome.
I only ever put about 1/4 of a tank of water in the thing anyway, thankfully.
I *think* they were supposed to put like a plastic cover sort of like what is on top of the decking but, there was none and so the plywood rotted from below. Never had a clue it was about to go.
This is a 2015 model so, if you have a Palazzo in that range you might check underneath and see if your compartments decking has a cover on it. I'm also adding what should have already been there, some angle to beef this up.