According https://help.minecraft.net/hc/en-us/articles/13803752803725 Chromebooks are now an officially supported platform. However attempts to install on the Pixelbook (i5, 8gb) fail as a plain search doesn't find minecraft. You can navigate to the install page by going via the Mojang company page on the Play Store however the game is listed as not compatibile.

I think ultimately this may be related to previous closed bugs which were collected under MCPE-32173 but as I can't re-open that so I'm raising this.