Google Assistant on Chrome OS is limited to Pixelbook at the moment. It does not have a proper integration with Chrome OS yet. On Pixelbook, Assistant launches as an additional layer.
My theory is that Google is still working on integrating the Assistant with Chrome OS, bringing it to the notification area, along with other apps. My theory is that we will see the Assistant on more Chromebooks when this work is complete.
Today I noticed one more code commit in this direction. This change adds Assistant icon to the search box of Chrome OS’ launcher. The change log simply reads:
Add assistant button in launcher search box
Further down in the code, we see this:
Once we have the new Assistant icon on the Chrome OS launcher (just like it does on Android phones), and the Assistant notifications are made part of the Chrome OS notification area, we will see a broader roll out of Assistant for Chromebooks.
That’s my educated guess. What do you think? Let me know in comments!