I understand the situation clearly as my 06 had to have the complete system replaced after a bad load of fuel, and the cost was well over $5,000. But that being said I still don't expect a vehicle to be designed to take into account every possible occurrence I might run into. If it were it would be $70k instead of $50k.
These trucks are designed to take into account the situations we might experience under "normal" day to day conditions. They are not designed (and I don't want to pay for) to clean up the mess made by the fuel station operator that does not properly maintain the filter and water separator on his pump, or the contractor who does the same. The people who have reported complete failures didn't just get a little water in their tank, they god a load of it, and it might not have been water either. That is what I have insurance for, and they can go after the guilty party.
And as a note, a dirty fuel filter can't strip water like it was designed to do, so diligent filter maintenance is my responsibility also.
A lawyer and a class action is only going to line the pockets of the law office, and do little to change the way the car or truck is built. Read the settlement agreement on almost any class action, and the consumer rarely gets anything, and the lawyer gets rich.