Graphics programming is not engine programming, although it can be viewed as a subset of it. Most large game studios have engine programmers that do very little graphics programming, if any. The majority of code in a game engine is not related to the renderer. I've worked in the industry on AAA and indie games and have worked in both roles, which are often different engineering teams.

I work in the industry now and had been since 90s. "Engine" roles, if exist, are for stuff like streaming, save/load etc. The thing described in TFA is graphics programming.