I don’t agree with what you state as the vulgar usage. “Graphics card” was the standard term a long time, even after they generally carried a (3D) GPU. Maybe up to around 2010 or so? There was no time when you had 2D-only graphics cards being called GPUs, and you didn’t consciously buy a discrete GPU if you weren’t interested in (3D) games or similar applications.

In the context of the discussion, the point is that you don’t need high-powered graphics hardware to achieve a fast GUI for most types of applications that WPF would be used for. WPF being slow was due to architectural or implementation choices.