Ya pays yer money ya takes yer chances. Couple hundred thousand cars to head for the cruncher. But I’ll guess they won’t be parted out.
You can bet your butt they WILL be parted. Parts like wheels, sheet metal, glass and many other parts will be just fine.
Electrical parts are the ones that will fail in a flood car.
You may have some rust problems with metal body parts.
Also each and every one of those cars will be headed to a salvage auction company like copart.