The drawing lib used by chrome is ridiculously performant - the problem is not at lower layers in case of modern UIs. Specific hardware will also be much more efficient than general purpose one, so no, gpus are not the culprit behind any of those.
While you may not like gradients, animations (which absolutely mandate GPUs) for example do give context on what happens because humans are used to physical objects that don’t teleport from one place to another. I wouldn’t consider these needless features either.
This is because said graphical applications are designed to be used with a modern GPU and they use stuff like OpenGL to render their components.
"but for gradients"
Maybe we can go without them. Modern UIs are too heavy, latency-inducing, battery consuming, and can turn your device into a heater easily.
"And 120, 240fps monitors are a thing now"
Re-drawing the window in every frame is a wasteful action that tends not to happen with applications designed for software rendering.