Out of curiosity, does Google contribute the drivers for Chromebook hardware to Linux upstream or do they keep it for themselves? Could it be that they just choose the hardware that works very well out of box with Linux?

I have no idea if there's upstreaming, but the Chomium OS repo is open source so you could check.

I don't know if that would help the wider Linux laptop community, because Chromebook OEMs can only select from a small list of CPU & chipset hardware combinations blessed by Google