Specifically, NVIDIA doesn't have the experience going for performance in the deep power management scheme required for laptops. Everything else they've done has been more about managing thermals while pushing for peak performance, or just throwing out a bunch of resources for the user to just figure out how to use. Mediatek, on the other hand, has no excuses. They've been making (crummy) processors for low end Chromebooks for a long time on top of their mobile phone, tablet and work for SoCs for Amazon fire devices.