Should my 1999 Mercedes-Benz be suffering from such extreme rust?

I have a 1999 Mercedes-Benz E320 CDI estate with 142,000 miles which is suffering from severe penetrated rust in the rear floorpan. I was put in touch with Mercedes-Benz Customer Relations who asked if it had always been serviced by a Mercedes dealer. I said that it had been until the last couple of years. He then informed me that I had violated the terms and proceeded to describe the type of rust that can occur on a car. He said it would be absolutely pointless in me pursuing this matter further. Although I have had a number of Mercedes cars over my 76 years this is by far the worst car for body rust that I have had the misfortune to own. It is my contention that, irrespective of the mileage, this type of extreme rust should not be acceptable on any car. I've attached photos for your information.
Unfortunately this is the Mercedes disease from around 1997 to around 2004. These Mercedes models seem to be more rust-prone than any other cars on the market during the same period. Mercedes-Benz is trying damage limitation by repairing cars up to eight years old, but denying any liability for older cars. In fact, Mercedes-Benz's liability in UK law ended when the cars were six years old. I’ve used some of your photos, together with those from other readers, in the E-Class entry in www.honestjohn.co.uk/carbycar
Answered by Honest John on

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