Do you have evidence to substantiate that claim?
I do. I have a letter from Dodge that was sent to me, and every other Viper owner in the fall of 2002. It stated that with the introduction of the all new 2003 Viper, Dodge would no longer be producing parts for the 2002 and older Vipers. They suggested you visit your Dodge dealer to "stock up" on any parts you think you might need. In less than a year, there were already people on the Viper forum pointing out that Dodge was out of different specific parts. Oddball stuff, like the trim piece on the door around the door handle. The rear glass for the RT10 models, etc. People with 2002 model Vipers did run into issues where there was a warranty claim, with no part available for that particular problem. I know Chevrolet ran into this problem with the 1990-1994 ZR1s. The engine made by Mercury Marine was the big issue, as they ran out of a lot of replacement parts for the engine as early as 1996.
I own a 1996 Viper (original owner). I can tell you FROM EXPERIENCE that everything that is shared on the Sky, like the engine, tranny, rearend, brake system, AC, etc, will be no problem what so ever getting parts to the end of time. However, I assure you, within just a couple of years (like 2), someone will post on here that they broke some little oddball part, and the GM parts computers are saying they have none in stock. I'll bet it will be a replacement seat cover for the Carbon Flash Sky that was a different color and was in a limited run anyway. Or the Door Panel for the Ruby Red Limited Edition that was in the special dark red color.
I just spent 4 *MONTHS* trying to get a specific HOSE for my Viper. Dodge is out of them. Someone on the Viper forum found one for a different car that would work. Radiator hoses have also gotten real hard to find, but an aftermarket company has recently started making them. They are high priced, but at least it is available.
The biggest issue for us Sky/Solstice owners is....We are in GREAT shape with our drivetrain. That is the stuff that will kill you on cost if you can't get it from a dealer. Our engines, trannys, and rearends are out of other GM products that are still being produced, so we are fine in that area.
Saturn stores are going out of business. Pontiac the brand will be gone in a year and a half. After that, the former "Pontiac/Buick/GMC" dealer will still be there, but will take down the Pontiac sign. Their staff, trained to work on the Solstice will still be there. They will still have the same parts inventory, tools, etc. It will probably suck like hell having to deal with a Pontiac dealer instead of the wonderfull care we get from our Saturn dealers, so get ready! My two local Pontiac dealers are SO HORRIBLE that is why I now own a Sky, to get away from them!