Right. And this was a mistake by Mozilla: they tried to make an OS, and a browser and interact/negotiate with 3rd-party phone vendors. I did not care for FirefoxOS-based phones indeed because they where "same old ridden-with-firmware black boxes".
Mozilla makes a good browser, they'd rather keep doing that.
Purism is a different story. It seems they understand that some folks appreciate open hardware, privacy-focused designs. Cool, one ingredient for the success: check. But in order to be a successful product, the phone has to be useful out-of-the-box. And if the hardware company will attempt to make a whole "native" software stack, they will fail the same way as Mozilla failed at being an OS-company and HW-facing company: not enough resources.
So, how about Purism makes a great hardware (+ drivers), and integrates exactly three apps: 1. a phone app that is able to make/receive calls, 2. a short-text messaging app 3. and a blazing-fast browser to access the world. Done. Basics are there: I can make calls, I can receive/send messages, I can access email, slack, hail uber/lyft, use web-based maps/navigation, listen to online podcasts/music, use web-based calendars, etc. A phone I could use everyday.
