The term "roadster"has been re interpreted here in the USA with more variation than a democratic lawyer in congress.

Even a big sedan can be called a "roadster"by some marketing people. Not sayin it's right but so what

Purist that I am says, a modern two seat vert is sufficient for the badge. But it must be a roadster with a stick to count.
But then as JHM2Kwould say, I just ain't right in the head.