Sure, but those only get rendered when stuff is actually changing on the screen, otherwise it stands still, compared to games which would (usually at least) continue to render N FPS no matter if the screen is identical or not compared to previous frame.

True, but nowhere near the level that a game would. As an example, it'll be hard to find a productivity/office application that is bottlenecked by the GPU, while for games, it's relatively easy to find.