I'm super grateful to Mozilla for trying. I think we'll eventually get to an open source web phone, but we're not quite there yet.
It's a tough market because as soon as you release something, there is a ticking clock until all of the low cost manufacturers release something cheaper and faster. Moore's law is not your friend when you're trying to differentiate a mobile product.
Beyond that general difficulty, a web phone faces some specific inevitable challenges:
1) No access to the "app world" of Instagram, Snapchat, etc
2) Can't optimize performance to the same degree
3) Web app access to hardware devices is limited
I think those are things you can't fight, you just have to accept them, but they are really hard to accept. This is the key psychological hurdle in any new web phone design project.
But let's get over them for a second and see what we're left with. The web also has some indominable advantages:
1) Instantaneous installation/startup of new "apps"
2) Long tail of web content can be a first class citizen in the UI
3) Novice-friendly development platform, i.e. "show source", embeddable HTML widgets, etc
4) Cloud-based by default
5) A community who will deploy infrastructure for free, so long as it is open source and decentralized
If I squint my eyes, I can imagine a web browser that really tries to capitalize on these things. From first principles, I think a development platform where the infrastructure for getting started is free-ish, apps and development environments all load instantaneously, data is never lost because it always lives in the cloud, emerging standards allow data to federate freely between services... you just float around allowing app access to your cloud data... such a platform would have substantial advantages over something like iOS or Android.
Those advantages may or may not be able to outweigh the inherent platform weaknesses I mentioned, but I can at least imagine it becoming a major player on mobile.
I think the trouble for Mozilla is there are still quite a few research projects there:
How do you federate data between services?
How do you host open source web apps in such a way that neither the programmer nor the end user has to be a sysadmin?
How do you make it easy to write performant, mobile friendly apps?
How do you organize a decentralized global community to adopt good usability practices?
How do you design a web browser so that web developers can make simple, fully integrated apps that fit into a more unified mobile experience?
I think if you could design something that at least solved all of these problems in a simplistic way—not fully robust, but a proof of concept with a few core apps, messaging, video, etc—and you really leaned in to the kinds of experiences that become uniquely possible on a platform like this, and then refine the shit out of it in an empirical Apple-style user-centered design tsunami, I think you might have a leapfrog product that could put Android and iOS on their heels.
Maybe.
If you could make it fundamentally easier to build and deploy web apps, you could get a huge store of long tail apps, which would form a kind of exclusive content moat. Not because those apps would be inaccessible on iOS or Android, but because they would be second-class citizens there.
To different extents Google and Mozilla have both been trying to tackle some or all of these research projects in different ways. But I'm not even sure if it's time yet. Maybe we just need to wait a little until some more of these answers shake out. Or maybe Mozilla just lacked the strategic vision to really know what to hammer hard on here.
But I am totally grateful to them (and Google) for trying. I still am drinking the Kool-aid. I still think the web is the future. Thousands of people are working on these problems all over the world. I think as Ethereum matures, it will fill in a lot of the gaps.
So, I think the Firefox can rise again. We'll see.