I don't understand why they are not required to carry the parts for 10 years. They sold the bikes in the US, and they included the pannier rails as standard on the 2011s (I think that was the year). Standard parts are supposed to be stocked for 10 years, and here we are a year or two later, and Triumph has abandoned their responsibility.
I tried to find a specific reference, and what I found instead was a lot of "myth" type of stuff suggesting that this is something that everyone in the US thinks is true, but may actually just be the policy of better importers and manufacturers.
So I guess its not specifically legally required, and Triumph is taking advantage of this.
Even if its not required, it sure seems like good policy to me. I wish Triumph would provide this level of support.