How well would the GameCube's more demanding titles, such as Metroid Prime, F-Zero or Twilight Princess, run on this CPU and its iGPU? Particularly in a fanless laptop like the Acer Swift 7, where the chip would be prone to throttling.
Would performance be better or worse than a smartphone with a comparable SoC, like the Snapdragon 821?
I'd say it'd probably perform better than a comparable chip in an android device simply because the x64 JIT is more mature. However, that doesn't mean they'd run well.
You might get a few light games working well, as it is a new Intel, and maybe some of the heavier ones will work until it starts to throttle, but not beyond that. If you want to run heavier dolphin games, a passive cooled laptop won't cut it.
I mean, passmark puts it on par as the G3258 @ stock but mostly sits around Core 2/Quads.. I wouldn't hope for much from what I'm guessing is a tablet CPU but it certainly wouldn't hurt to try some of the lighter games out.