unwat
Many of the privacy-focused desktop OSes have significantly reduced functionality and poorly-designed UIs. Popular Linux distributions don't count in this instance, since their security is questionable.
The extreme variety of devices that support ChromeOS and could also support my proposed OS is a very valid point. GOS devs obviously have very specific hardware requirements. I'm not sure if laptops allow for hardware-based isolation of Wi-Fi, GPU, encode/decode, etc. I wouldn't doubt that such a thing exists, however.
As far as I'm concerned, the firmware (for Pixel devices at least) is part of the AOSP, so telemetry can be removed. I'm not sure how this works on Chromebooks.